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Fire Risk Assessment

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New rules for blocks over 11m will affect Airspace development.

Posted by wilkinsoncc on May 26, 2020 at 8:35 AM Comments comments (0)

The Government have today (26th May 2020) published new guidance that will require Sprinklers and Way finding signage in blocks of flats over 11m in height.

Critically this will also apply to airspace development where stories are added to an existing block.

The new rules require that blocks of flats with a top storey more than 11m above ground level  should be fitted with a sprinkler system throughout the building. Sprinklers should be provided within the individual flats, they do not need to be provided in the common areas such as stairs, corridors or landings when these areas are fire sterile.

Applicants and building control bodies are reminded of the need to consider these new provisions in relation to extensions as required by Regulation 4(1).

New accommodation, formed by building work, should meet the relevant requirements having considered the guidance in the approved document. This means ensuring that the standard of fire protection for the occupants of the new accommodation is as would be provided for a new building under the approved document.

In the majority of cases, therefore, sprinkler protection and wayfinding signage will be necessary in any newly formed accommodation that falls above the new 11m trigger height.

It may also be necessary to consider additional protection for the existing parts of the building where needed to ensure that the extension is compliant with the applicable requirements of Schedule 1.

Equally, it will be necessary to satisfy regulation 4(3) by ensuring that the level of fire protection in the building as a whole is made no worse.


The 2019 edition will continue to apply where a building notice or an initial notice has been given to, or full plans deposited with, a local authority before 26 November 2020 and either the building work to which it relates:
a. has started before that day; or
b. is started before 29 January 2021.

The changes focus on the following fire safety provisions in blocks of flats:

a. Sprinklers:A reduction in the trigger height from 30m to 11m.
b. Wayfinding signage for the fire service: A new recommendation for floor identification and flat indication signage within blocks of flats with storeys over 11m

The full guidance can be found https://www.gov.uk/government/publications/approved-document-b-volume-1-and-2-circular-012020?utm_source=73556982-aab9-4856-8879-1cbda3f61bb0&utm_medium=email&utm_campaign=govuk-notifications&utm_content=immediate " target="_blank" rel="nofollow">here

Return to work

Posted by wilkinsoncc on May 11, 2020 at 10:20 AM Comments comments (0)

Return to work

The construction industry is rapidly returning to work following the Prime Ministers announcement last night (10th May 2020).

This raises a number of issues regarding the health and safety of workers on the construction sites which are quite rightly being discussed on social media today.

However, one aspect that doesn't seem to have been considered is the problem of "material substitution", where one product is changed for another. 

With builders merchants and manufacturers still closed in full or part contractors will struggle to get the materials they need to undertake the work that's required. If they cant complete the work they will often have penalty clauses for late completion or simply not get paid for the work that they have partially competed. This places them under great pressure to "get building work done" and it becomes increasingly tempting to substitute one product or material for another. 

Whilst changing the colour of a kitchen worktop has little effect on health and safety other material swaps can have major life safety implications. This was evidenced dramatically at Grenfell Tower where cladding and insulation materials were swapped from the original product specifications, resulting in multiple deaths. To many contractors (and builders merchants alike) one product may seem very much like another, and the temptation to swap from PIR (polyisocyanate) insulation to PUR (polyurethane) insulation if that's all that in stock will be great. However, if that product hasn't been tested in the same combination as the original it may simply not be safe to use. 

In some cases the products being substituted may look visually the same but have significantly different properties. Just last month CROSS (the whistleblowing scheme for construction safety) carried a warning that concrete lintels in a domestic extension had been wrongly substituted. The report explained that the engineers designed lintel was swapped with an alternative from the same supplier. The geometry of the two lintels were identical, but the replacement lintel was only designed to take 3/4 of the load of the original, risking future structural collapse.

In recent days we have seen builders intending to render directly onto OSB rather than a cement particle carrier board (risking warping and damp ingress), another who "sealed up" a manhole with a sheet of insulation and tape (risking the entry of raw sewage) into the building and one who installed of a domestic smoke detection system where a commercial system was required to ensure fire safety. Other examples include swapping fire or moisture rated plasterboard for standard plasterboard or using standard concrete instead of sulphate resisting concrete. 

There is a real risk that this is common place, and likely to increase with hidden defects not becoming apparent for several years in some cases. Now more than ever it is important that works are fully inspected and that you look to appoint a clerk of works to check that the correctly specified materials are in place. Reliance on Building Control inspections alone will not deliver quality or safety as many of these items may not be identifiable and are often not "statutory" inspection stages in any case.

The issue of materials substitution was raised in Dame Hackitts report where she recommend that firstly a detailed specification must be approved prior to works commencing (known as Gateway 2). To avoid substitution she also recommended a statutory change managment system whereby changes of materials legally had to be notified to Building Control and works are not allowed to continue until that change had been approved. Lastly prior to occupation the contractor is required to evidence that the correct products had been installed by competent people. 

To avoid the risks of material substitution the Government needs to ensure urgently that stocks of products are back to pre-COVID levels in order to safeguard lives. We would also call on Government to bring forward Dame Hackitts recommendations and legislate that 


  • that work cannot start until approval is in place, 
  • that material substitutions must be notified to Building Control and
  • that materials are clearly marked to help identification 
We would also ask that this applies to all projects (including domestic extensions) and not just to buildings in the scope of Dame Hackitts report (eg those over 18m in height). Whilst this might seem a draconian measure pre approved specifications could be published to speed up the approval process - indeed a similar website already exists at www.Buildingregs4plans.co.uk which enables even a small builder to produce a compliant specification in minutes.

Pending that legislation we need an urgent national campaign to educate contractors, surveyors and clients of the risks and what to look out on site to prevent incorrect material use. 


Building A Safer Future - Draft Reply

Posted by wilkinsoncc on July 30, 2019 at 6:45 AM Comments comments (0)

As promised here is our draft response for you to use and amend as you wish.

Building safer future





Time is of the essence as the consultation officially closes on 31st July but I’m sure they will accept responses at least until Friday and may even announce an extension of time.

When you are ready add your name and sign the last page (electronic signature is fine) then Email to BuildingSafetyConsultation@communities.gov.uk and Copy to esther.mcvey.mp@parliament.uk

Want to know more check out our video https://youtu.be/NJ7LXfgXFPw

Building A Safer Future - Quick Guide

Posted by wilkinsoncc on July 23, 2019 at 8:30 AM Comments comments (0)

This guide tries to explain the key points from the Governments huge 198 page consultation on fire safety in high rise buildings (see https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/806892/BSP_consultation.pdf)

The government are particularly keen to hear what people who live in high rise buildings think about the proposals, and you dont have to use the official response document, as they have promised that "All responses will be read and analysed, regardless of the format used". To help we will also publish our draft response over the next few days that you can cut and paste for your own response. Please take the  time to do this as we need as many people to respond so that its not just the same old voices being heard.

You can respond online using this link if you dont want to wait https://www.surveymonkey.co.uk/r/BuildingSafetyConsultation

Heres a quick overview of the consultation

Chapter 1: Introduction and progress to date

This chapter sets out what the government has already done and is currently doing to make buildings safer - you can skip this bit.

Chapter 2: Types of buildings we want to include in the new system

The new building safety regime will only be for buildings that are

• lived in by multiple households; and 18 metres high (roughly 6 storeys) or more.

To answer a question on this proposal, see Question 1.1 at paragraphs 28 to 34 on pages 28 to 29 of the consultation document and Questions 1.2 - 1.8 at paragraphs 35 to 52 on pages 29 to 33.

Chapter 3: A new dutyholder regime

Part A deals with proposed buildings

Dutyholders will be responsible for ensuring that building regulations – the minimum standards a building must meet – are complied with at new ‘gateway points’ before they can continue with the different stages of the building process.

o Gateway 1 – before planning permission can be given, the dutyholder will need to submit a ‘fire statement’ to the Fire and Rescue Authority.

o Gateway 2 – before construction can begin, the dutyholder will need to get full plans approved.

o Gateway 3 – before anyone can move into the building, the dutyholder will need to hand over building safety information about the completed building. They will need to apply for and receive a provisional registration of the building and tell the regulator that building risks have been assessed and arrangements are in place to make sure the building is managed safely while people are living there.

To answer questions on this proposal, see Questions 2.1 - 2.33 at paragraphs 59 to 107 on pages 35 to 48.

Part B deals with existing buildings and requires a ‘safety case’ setting out how the building is being kept safe and it is clear who is responsible for keeping the building safe.

The accountable person may also employ a ‘Building Safety Manager’ who would be there to deal with any safety problems they find or are reported by residents in the block(s) they are responsible for.

To answer questions on this proposal, see Questions 3.1 - 3.22 at paragraphs 108 to 194 on pages 49 to 65.

Part C sets out the duties that run through the building’s life cycle and requires a set of key documents held digitally on building information. This could include information on the structure of the building and any changes made to the building through refurbishment.

A system of ‘mandatory occurrence reporting’ to the regulator which will ensure that the client, principal designer, principal contractor and accountable person must ensure that anyone involved in the construction of a building can report fire and structural issues.

The new system will make sure that all dutyholders employ people who are suitably qualified and competent eg has the necessary skills, knowledge and behaviours to make informed decisions and carry out their job effectively.

To answer questions on this proposal, see Questions 4.1 - 4.20 at paragraphs 195 to 243 on pages 66 to 78.

Chapter 4: Residents at the heart of a new regulatory system

These proposals will give residents a stronger voice and allow them to hold those responsible for the safety of their buildings to account. Residents will be empowered by having better access to information about their building and have more of a say over decisions made about the fire and structural safety of their building.

To answer a question on this proposal, see Question 5.1 at paragraphs 252 to 255 on page 81.

Residents will also be able to access more detailed information about building and fire safety by requesting it from the accountable person. The accountable person will only be able to refuse to provide information for specified reasons (e.g. that sharing the information would be a security risk or would divulge personal information).

To answer questions on this proposal, see Questions 5.2 - 5.3 at paragraphs 256 to 261 on pages 82 to 83.

The accountable person must have a Resident Engagement Strategy which sets out the way that they are going to engage with residents and how residents can get involved and benefit from participating in engagement on building safety.

To answer questions on this proposal, see Questions 5.4 - 5.5 at paragraphs 262 to 271 on pages 83 to 85.

In some cases individual residents may put themselves and their neighbours at risk. The government are proposing that there is a clear obligation on residents to co-operate with the work of the accountable person to keep the building safe and are asking for views on the obligation and what safeguards would be needed.

To answer questions on this proposal, see Questions 5.6 - 5.8 at paragraphs 272 to 278 on pages 85 to 86.

To make sure that residents can raise safety concerns, the accountable person will need to have a clear process for how they will respond to residents’ concerns.

To answer a question on this proposal, see Question 5.9 at paragraphs 282 to 284 on pages 87 to 88.

Residents will be able to take urgent safety concerns to the new regulator if the accountable person fails to deal with them properly.

To answer questions on this proposal, see Questions 5.10 - 5.11 at paragraphs 285 to 291 on pages 88 to 89.

Chapter 5: A more effective regulatory and accountability framework for buildings

The Government propose a new building safety regulator to ensure these changes are enforced robustly and effectively.

The regulator will also oversee the wider building and regulatory system and work to drive high standards of competence for those working on buildings.

To answer a questions on these proposals, see Questions 6.1 - 7.4 at paragraphs 300 to 334 on pages 91 to 98.

The government are also proposing that there should be stronger regulation of construction products – eg insulation and cladding products

To answer questions on these proposals, see Questions 8.1 - 8.15 at paragraphs 335 to 356 on pages 99 to 104.

Chapter 6: Enforcement, compliance and sanctions

Through strong oversight by the new regulator, those responsible for the safety of buildings must comply with their responsibilities or be held to account if they do not.

The government are proposing to:

• Create new criminal offences to make sure that those responsible for the safety of a high rise residential building during the design and construction of the building, as well as when residents are living in the building, comply with their responsibilities;

• Give the new regulator the power to take quick and effective action, through monetary penalties such as fines, when the requirements of the new regime have not been met.

To answer questions on these proposals, see Questions 9.1 - 9.4 at paragraphs 357 to 364 on pages 105 to 107.

The government are also proposing to make it easier to take action for all buildings where building work does not meet required building regulations standards by:

• Giving local authorities more time to serve enforcement notices, so that they can take action where problems are uncovered later; and

• Enabling private individuals to make a claim for damages where work on a building has not met building regulations standards, and they have suffered harm as a result.

An enforcement notice is a legal document requiring a particular action to be taken when there has been a breach of planning rules.

To answer questions on these proposals, see Questions 9.5 - 9.6 at paragraphs 365 to 373 on pages 107 to 108.

Office Fit Outs - The Regs

Posted by wilkinsoncc on November 12, 2018 at 8:00 AM Comments comments (0)

The Regs: Take safety into account when designing partitions

Geoff Wilkinson looks at the fire safety rules relating to alterations to offices

One of the questions we regularly get asked is whether or not Building Regulations apply to minor works to fit out offices, shops, and so on. In most cases the answer is ‘yes’ and there are quite a few regulations that you can fall foul of if you are not careful.

It will come as a surprise to many architects that even a simple project to subdivide an office can require building control approval. This is because the regulations apply to any alteration that affects the means of escape in case of fire, even if it there is no structural work proposed. Conversely, taking down partitions to make an open plan office can also require permission, as the partitions may have formed a means-of-escape corridor or other form of protected escape route.

A typical scheme might involve creating a new office or meeting room within an existing open plan layout. This is known as an inner room, and specific rules apply, as the only escape route is through another room and a fire in the outer room could trap someone inside. Therefore, Building Regulations require that:

• the capacity of the inner room does not exceed 60 people (which could rule out meeting and conference rooms)

• the escape route from the inner room should not pass through more than one outer room

• the travel distance from the inner room to the exit(s) from the outer room should be limited (usually to 18m in total)

• the outer room should not be a place of special fire hazard

• the outer room should be in the control of the same occupier; and

• in order to give early warning of a problem, either

1. the partitions of the inner room should be stopped at least 500mm below the ceiling, or

2. a vision panel not less than 0.1m2 should be located in the door or walls of the inner room, or

3. the outer room should be fitted with automatic fire detection which is audible within the inner room.

Other considerations include:

• changes to the emergency lighting and fire exit signage may be required

• changes to sprinklers or fire detector locations may be required

• wall and ceiling linings should be controlled and the surface spread of flame rating limited.

Note that if you are dividing a floor into separate occupancies, the means of escape from each occupancy should not pass through any other occupancy. If the means of escape will then include a common corridor or circulation space, then either it should be a protected corridor or a suitable automatic fire detection system should be installed throughout the whole of the storey.

Therefore plans should always be prepared for building control approval which show the following: proposed uses of each space; fire escape routes; fire compartmentation; cavity barriers to floors and ceilings; fire rating of doors and partitions; proposed ironmongery; fire alarm layouts; exit signage; emergency lighting; and sprinkler layouts (these are often best shown on a reflected ceiling plan).

This article originally appeared in the June issue of AJ Specification


Photo (C) www.rapinteriors.co.uk/

Response to Dame Judith Hackitts Final Report

Posted by wilkinsoncc on July 30, 2018 at 7:55 PM Comments comments (0)

Response to Dame Judith Hackitt’s Final Report

Following the publication of Dame Judith Hackitt’s Final Report, ‘Building a Safer Future: Independent Review of Building Regulations and Fire Safety’, the Government asked to hear views as to how these recommendations should be taken forwards.We believe that the report does not go far enough and that we need "Hackitt Plus"

We have today responded to the report and provide a summary of that response below.

Recommendation 1.1

We do not agree with this recommendation as we feel that the system should apply to all buildings, and a two-tier system will cause confusion. Whilst we note the scope of Dame Hackitt’s report was framed by Grenfell, but we do not agree that statistics show an increased risk with height. If we review past tragedies such as Summerland, Woolworths, Bradford & Kings Cross , none of these were High Rise buildings. Additionally, far more people die every year in low rise domestic buildings than in High Rise buildings – a fact previously confirmed by the National Fire statistics.

A 10 Storey limit could have other unintended consequences and encourage developers to demolish existing buildings over this height or abandon plans to build them in favour of 9 ¾ storey buildings to avoid the additional burden. This would fly completely in the face of the wishes of existing residents who want their buildings to be safe not to be demolished and rehomed.

If a definition of high risk is to be applied we would consider that it is probably better to link it to the possibility of multiple fatalities, therefore the application of increased burden could apply to any building with an excess of 60 or 220 persons in line with the limitations in ADB.

We would also advise against the term High Risk buildings as this has significant negative connotations in the minds of the public. Possibly the use of High Occupation or Increased Dependency may be better terms.

Recommendation 1.2

We support the setting up of the JCA, but would advise that the JCA should be a separate enforcement body and repository for notices and data rather than being a service provider.

Recommendation 1.3

We strongly agree with the provision of a new user manual.

Recommendation 1.4

We have no comment to make on this recommendation, other than to suggest that it is separate from the BCB service provision – thereby enabling concerns to be raised about BCB’s.

Recommendation 2.1 & 2.2

We agree that these should be clearly mandated to explain responsibilities and that CDM is a good basis for these.

Recommendation 2.3

We agree that these should be provided for all high-risk buildings. We would also like to see simpler versions provided for all building Projects

Recommendation 2.4

We believe that there should be a single system with tiered requirements for detail rather than multiple systems.

Recommendation 2.5

We agree that the LPA should be required to notify the JCA – however we believe this should apply to all building work covered by planning permission. The notification should confirm that a BCB has been appointed and is overseeing the scheme and that the BCB has/will consult with the fire service. Until a copy of that consultation is deposited with the LPA an unconditional planning approval cannot be given.

It should be remembered that internal works notifiable under Building Regs and CDM may be exempt from Planning Permission and this would make the first Gateway redundant on a scheme to say replace all the kitchens and fire doors in a block.

Recommendation 2.6

We absolutely agree that works should not commence prior to a full plans approval. This is probably the single most important of all the report’s recommendations in our opinion. However, the JCA should not be a service provider and instead the requirement should be that a BCB provides a copy of the full plans approval to the JCA, otherwise we would be concerned that the JCA would be overwhelmed.

We would like to see this extended to all projects and additionally that the JCA gets a copy of the F10 and construction phase risk assessments. This is because the construction phase can be the highest risk especially if occupants remain in place. We believe that this would also be useful on minor projects such as domestic extensions.

The CITB app has produced a simple way for small builders to comply with CDM and the https://www.buildingregs4plans.co.uk/index.php website could easily be adapted to enable builders to produce simple compliant plans and specifications, which would not cause undue burden.

Recommendation 2.7

We agree that buildings should not be occupied until a final certificate, O&M, demonstrable records and the FRA are in place. The JCA should have an obligation to enforce if this cannot be evidenced.

Recommendation 2.8

As above we consider that the Gateway points should apply to all building projects. There should be optional boxes for the situations where Planning, Building Regs & CDM apply different definitions, but the concept should be universal.

Recommendation 2.9

We agree that there should be a clearer change management process for all buildings. Any change to the previous approval should be considered by the BCB and notified to the JCA where significant.

Recommendation 2.10

As previously stated all works should be notified to the JCA. To suggest that only a JCA incorporating LABC should oversee the works would mean that something as simple as a resident rewiring a kitchen or installing a power-shower would require the involvement of the JCA. This is likely to result in either severe delay, additional cost or more likely both. If instead the CP had to provide a detailed plan showing any fire safety features, specifications of work, risk assessments and evidence of the completed works there is no reason in our opinion why self-certification could not continue.

Recommendation 2.11

We do not agree with this recommendation as previously explained. AI’s are already prevented from having a financial or design interest in a project. LABC do not have such limitations and are already marketing additional products such as SAP calculations which they submit to themselves for approval https://www.labc.co.uk/consultancy-services. Regardless of the outcome of the review we would ask that it is made clear that it is not acceptable for any BCB to submit documents to itself for review, even if that is produced within a group structure. It should also at the very least be recognised that LABC are conflicted by being employed by the owners of their own buildings and not independent in the way that’s being presented. Indeed, both Lakanal House and Grenfell exposed this clear conflict of interest. Therefore, we would urge that the JCA should be a separate national body, recruiting its own staff/experts to avoid any risk of conflict.

Recommendation 2.12

We make no comment on this recommendation

Recommendation 2.13

We strongly support this recommendation. We also feel that having the JCA independent of LABC would result in greater consistency as we would expect that organisations flouting Building Regulations would typically also be flouting CDM & Fire Safety and even planning approval.

Recommendation 2.14

We agree that the first work on an existing “high risk” building (Subject to how that is defined) should trigger a safety case review if that is not already in place.

However, we would also propose an alternate proposal that all building works should trigger consequential improvements whereby 10% of a projects value should be ring fenced to addressing any deficiencies in fire safety. This could easily be addressed by reviewing the existing FRA and money spent on upgrades. For example, a proposal to replace the windows in a block would trigger a requirement to spend at least 10% upgrading any existing non-compliant fire doors, or installing smoke detectors, or some similar upgrade. This concept already exists in AD L and would create a culture whereby all building work considers the safety case first.

Recommendations 3.1, 3.2, 3.3, 3.4 3.5, 3.6, 3.7, 3.8,

We agree with these proposals in full (but note previous comments about the composition of the JCA)

Recommendations 4.1, 4.2, 4.3 , 4.4, 4.5, 4.6

We agree with these proposal’s but additionally feel that all buildings should display a summary A-F style FRA in the same way as an EPC is displayed. This is likely to drive owners to want to improve ratings. It could also be used to prevent the sale or rental of buildings falling below a minimum (Say E) rating.

Recommendations 5.1, 5.2, 5.3, 5.4

We agree with these proposals

Recommendation 6.1

We agree with the concept, but the emphasis should be reversed, and the Government must validate guidance produced by industry. The creation of the flawed BCA guidance note 16 on cladding shows how confusing industry generated guidance can be.

We would also see that this is part of the function of the JCA rather than “Government”. We strongly recommend the JCA provide FAQ’s and possibly live chat to help point BCB (or designers) to the correct interpretation.

We are aware that previous civil servants have deliberately acted to make it difficult to get advice, guidance and determinations with the consequence that there is inconsistency in interpretation and even competition on interpretation which does have the capacity to drive standards to the lowest level.

Recommendations 6.2, 6.3

We agree with these proposal’s and are working to produce an easy to use app and would be more than happy to demonstrate this further.

Recommendations 7.1, 7.2,7.3, 7.4, 7.5, 7.6, 8.1, 8.2, 8.3 , 8.4

We agree with these recommendations but would go further. We believe all products should be capable of being scanned by smart phone with GPS recording to confirm the exact details, batch numbers, the installers signature/qualification, and the location the product is installed in the building. 

Recommendation 9.1, 9.2, 9.3, 10.1

These recommendations are outside our scope of expertise and we make no comment

Resources Generally

In addition to the recommendations made above we have significant concerns about the current levels of resources and competencies of BCB. Despite claims from LABC that they have the resources it is our opinion that the system is already over stretched.

We are also concerned that it is assumed that AI’s will offer support to LA services. In most cases AI’s left employment by LA as they did not want to work in the public sector, we cannot see them returning to that sector. It is also likely that the nature of LA procurement will mean that SME would be unable to compete with larger organisations to provide this back up. Its likely that organisations such as Capita, Interserve etc will see this as an opportunity to add to their existing service provision to LA. This would result in the unintended consequence of outsourcing BCB functions and could risk another “Carillion” collapse.


Overall, we feel that the report is a significant move forward building on the 2009 Future of Building Control Implementation Plan, and BD2510  Scoping report on MOT tests for buildings.However, it is important that we do not wait another 10 years before actioning the recommendations.

Our prime concerns are the role of the JCA, the confusion a two-track system would create, and resources generally. We have set out alternate solutions on these issues and would be happy to discuss them further if the opportunity arises. We look forward to seeing Hackitt Plus being implemented in due course.

The Regs: Take care when building over drains and sewers

Posted by wilkinsoncc on July 30, 2018 at 8:30 AM Comments comments (0)

Geoff Wilkinson looks at problems arising from failure to identify where drains run

One of the most frequent problems we see with small projects arises from the failure to check whether or not there are drains running beneath the footprint of a proposed building or extension.

Building Regulation H4 requires that when building within 3m of a public sewer, or within 1m of a public lateral drain, you’ll need water authority approval before work begins. Even if the drain is not a public sewer or shared drain, failure to identify the location of the drain can still cause major issues if there is a conflict between the line of the drain and the line of the structure above.

Failure to identify the depth of the drain can also cause problems. A shallow drain might be too shallow to enable drainage from the new project to function correctly, or it might clash with the floor slab. Equally, a deep drain might require significantly deeper foundations than were originally assumed or priced for.

The RIBA Plan of Work for small projects places the production of drainage plans in Stage 4, but this is too late if the drains are found to clash with the building – which can require a full reapplication to be made for planning permission.

Instead I would recommend that a search for the location of drainage should be conducted at Stage 2, when the feasibility of the project is considered, and prior to obtaining a planning consent that may simply not be buildable.

Access points on a sewer may need to be relocated as part of the works and included in the design

It should be remembered that the Building Regulations state that in some soils, such as sands or silt, buildings must not be constructed over or within 3m of a drain unless special measures are in place.

Additional restrictions apply if the drain is a rising main, constructed of brick (a traditional Victorian culvert, for example), or if it is damaged or in poor condition.

Buildings and extensions should not be constructed over a manhole or inspection point on a sewer. Access points on a sewer may need to be relocated as part of the works and included in the design. The extension must also maintain a 3m zone to enable the sewer to be reconstructed in the future if the water authority deem it necessary, and that zone should also be accessible to a mechanical excavator, depending on the depth of the drain.

Building Regulations also restrict the length of drain or sewer that can be built over to a maximum length of 6m.

Lastly, if the drain is greater than 225mm in diameter or greater than 3m in depth, then again special consent will be required, which could affect the viability of the project.

In most cases applying for permission is simple and can be done using a self-certification questionnaire online, although some water authorities are much more helpful than others and a simple national system would help remove regional variations. If you aren’t able to self-certify, you can instead apply for an approved build-over agreement, which should be supplied to the Building Control body prior to the works commencing.

If a build-over agreement is required, then a number of important restrictions are likely to apply. These vary by water authority, but typically include:

  • All new works must be done in like-for-like materials and comply with the requirements of the latest version of ‘Sewers for Adoption’, in conjunction with ‘Protocol on Design and Construction of Adoption of Sewers in England and Wales’. For example, plastic drainage may not be acceptable if the existing drain is manufactured in clay.
  • The proposed works must not transmit any additional loads to the sewer, and foundations must be taken below the invert (internal pipe base) level.
  • It is your responsibility to check and verify the invert levels and position of the public sewer prior to works on site.
  • Any sewers that are up to 1.1m deep from ground level to invert must maintain a minimum 150mm gap away from the foundations.
  • Any sewers where the invert level is more than 1.1m below ground level must run at least 500mm away from the foundations.
  • If the invert level is more than 2m below finished ground level, any proposed foundations must be at least 1m from the sewer.
  • Piled foundations must be a minimum of twice the pile diameter or 1.5m (whichever is greater) from the outside of the pile to the outside of the sewer.
  • Driven piles are not permitted within 15m of a public sewer.

So: don’t leave it too late in the project to check where the drains run; ideally, pick it up during the initial site survey.

This article originally appeared in the May issue of AJ Specification


Illustration (C) Thames Water Utilities Ltd https://developers.thameswater.co.uk/Domestic-and-small-commercial/Building-near-pipes/Building-over-or-near-a-sewer

The Regs: How to get a highly glazed extension to comply with Building Regulations

Posted by wilkinsoncc on June 15, 2018 at 11:15 AM Comments comments (0)

The Regs: How to get a highly glazed extension to comply with Building Regulations

If you have ever wondered how an architect got that glass box extension past building control, then Geoff Wilkinson has the answer

There has been a huge trend in demand for extensions that join internal living spaces to the garden by way of large areas of glazing and ever larger opening bi-fold doors. However this sleek and transparent look desired by homeowners can be at odds with Building Regulations Part L, which sets targets for the building envelope’s energy efficiency.

Part L limits the total area of openings or glazed elements, such as windows, roof windows and doors, to a maximum of 25 per cent of the extension’s floor area. A small extension with a set of patio doors and a lantern light can easily use up this 25 per cent allowance.

An extension that exceeds the allowance is generally referred to as an ‘over-glazed extension’, but they can also be known as sun rooms, orangeries or even glass-box extensions.

Architects will find that, where the 25 per cent rule is exceeded, building control will either reject the plans or request further justification for the over-glazing. So how do you get an over-glazed extension to comply?

Well, although the extension is not compliant on an individual element basis, it could still pass L1B regulations using one of the alternative methods set out in the approved document.

The first thing to do is to deduct the total area of any windows or doors that, as a result of the extension works, no longer exist or are no longer exposed. This is because the heat lost through these elements is no longer being lost. In many cases you will find that this is all you need to do, and a quick schedule of openings versus covered openings may be all that you need.

For example: if an extension has a floor area of 30m² and is covering an existing patio door with an area of 4m² then the extension is allowed to have 6m² (25 per cent rule) plus 4m² (existing openings rule) making an allowable area of 10m². Submit that with your Building Regs application and it’s likely to sail through the checking process.

But if this still isn’t enough then the next option is to demonstrate that the proposed extension is no less compliant than if an extension of the same size and shape was built according to the 25 per cent limit. For example, you could increase the thermal resistance (U-value) of the walls, floor, roof, or glazing elements above the default values in order to increase the area of glass.

From experience I can say that in most cases the heat loss though the glazing will dominate, so start there. Given that the default U-values for walls, floors and roof should all be in the range 0.16-0.28W/m2K, there is not much you can do to significantly improve these. However, the notional glazing has a U-value of 1.6-1.8W/m2K and means that high-performance, gas-filled, low-e-coated glass could see the U-value tumble to 0.9 or better, allowing you more than 40 per cent glazing. Take out some covered-up openings and a 50 per cent glazing ratio is easy to achieve.

But if the extension is very highly glazed (more than 50 per cent), you may need to use the Standard Assessment Procedure (SAP). These calculations should be carried out by an accredited SAP assessor, and demonstrate that the calculated carbon dioxide (CO2) emission rate from the dwelling with its proposed extension would be no greater than the dwelling and a notional fully compliant extension of the same size and shape. This method allows you to keep almost 100 per cent glazing by upgrading existing elements and services within the original part of the house instead – for example, by installing a more efficient heating and hot water system, or increasing the insulation within the existing roof space.

The SAP method allows you to keep almost 100 per cent glazing by upgrading existing elements within the original part of the house

The building control officer may well confuse matters by asking for ‘excess glazing calculations’, ‘SAP calculations’, ‘heat loss calculations’ or ‘thermal calculations’, but in truth all four terms mean the same thing. If you are not qualified to carry out these calculations yourself then I would recommend Googling ‘heat loss calculations for over-glazed extensions’ and you will find a number of consultants that can produce them for you.

In many cases it’s only a couple of hours work for them and a budget of £250 can usually cover it – a small price to pay for that award-winning, highly glazed look on your project.

This Article first appeared in Architects Journal https://www.architectsjournal.co.uk/opinion/the-regs-how-to-get-a-highly-glazed-extension-to-comply-with-building-regulations/10022424.article

Chloes Wedding

Posted by wilkinsoncc on May 31, 2018 at 7:55 PM Comments comments (0)

Congratulations to our longest serving employee Chloe Still on her marriage to Dave Prentice on 24th May 2018.

The Wedding took place in the fantastic venue at the Lost Village of Dode and even featured both a Owl and a Magician.

We wish them both the very best for thier future together

Dont get your fingers burnt on a kitchen project

Posted by wilkinsoncc on May 29, 2018 at 8:40 AM Comments comments (0)

The Regs: Don’t get your fingers burnt on a kitchen project

Geoff Wilkinson looks at the potential pitfalls of kitchen, utility and bathroom schemes

Work to a kitchen, utility room or bathroom can seem like the simplest of projects an architect can deal with, but they can be a minefield if you aren’t sure when you need Building Regulation approval.

A very simple refresh with new units and fittings does not generally require approval, however moving sanitary fittings such as the sink or toilet or carrying out electrical works as part of a refit may do so.

Source: Agnese Sanvito

Whitehill Farm, Dunstable, by Hampson Williams Architects

If a bathroom or kitchen is to be provided in a room where there wasn’t one before or you are knocking down a wall (loadbearing or not), Building Regulations approval is likely to be required to ensure the room will have adequate ventilation and drainage, and meet requirements in respect of structural stability and electrical and fire safety. If in doubt always check with a building control body – either the local authority or an approved inspector. Here’s a quick guide to some of the pitfalls to look out for:

Part A Apart from the obvious issues of removing a structural wall, if you are changing the use of a room (eg installing a large bath or jacuzzi in a bedroom) this could increase the load on the floor structure and require strengthening the floor.

Part B Making an open-plan space by removing doors or walls between the kitchen and other rooms, particularly to a staircase, will affect means of escape. Additional precautions in other parts of the property may be needed, such as escape windows, interlinked smoke and heat detection, additional fire resistance or even sprinklers.

Part F When inserting or removing an internal wall, care should be taken not to make ventilation worse. Any new kitchen, a toilet with no openable window; a bath/shower room or utility room should be provided with a mechanical extract fan. The type of room will determine how much ventilation is required. Part F says that where a kitchen previously had only a recirculating fan this can be retained/replaced if it is made no worse. However, I would always recommend fitting an extractor to deal with condensation.

• Kitchen: 30l/s if over the hob and 60l/s if placed elsewhere

• Bath/shower: 15l/s with overrun

• Toilet: 6l/s with overrun

• Utility room: 30l/s

Part H Replacing existing fittings on a like-for-like basis is not controlled. However, if the installation of the fittings will extend or make new connections to a drainage stack or an underground drain, the above-ground wastes and drains are controllable.

Part L If you install or replace a window or external door as part of the works, it will need to comply with Part L Heat Loss in all cases. It may also need to comply with Part A Structure if the opening is made wider; Part K Safety Glazing if the glass is at low level; and possibly Part B Fire Spread if the glass is within 1m of the boundary, for example.

Part J This obviously applies if you install a new boiler, but also if you move the boiler to another location or even if you leave the boiler where it is but extend the flue. Also, if hiding a boiler in a cupboard, take care to ensure there is adequate ventilation and access for servicing.

Part M Another area where you may get caught out is simply moving a ground-floor toilet, since most houses constructed after 1999 will have a ground-floor toilet installed, which has been designed to cater for any visiting wheelchair users. During any refitting, this toilet should not be removed and the accessibility of the toilet should not be made any worse, as it would then be inadequate for future wheelchair users.

Part P Electrical work may be non-notifiable unless a new circuit is provided. For example, installing a new built-in cooker or prefabricated modular lighting is non-notifiable unless a new circuit is required. Even so, be wary of affecting:

• structure (depth of chases in walls, notches in floor and roof joists)

• fire safety (fire resistance of penetrations through floors and walls)

• sound (service penetrations on party walls)

• replacing energy-efficient lighting with inefficient lighting

If a new circuit is being installed or it is within a wet zone (eg adjacent to a bath or shower) then it will require approval or self-certification under Part P.

This article originally appeared in the https://www.architectsjournal.co.uk/opinion/the-regs-dont-get-your-fingers-burnt-on-a-kitchen-project/10031324.article#" target="_blank" rel="nofollow">April issue of AJ Specification