|Posted by wilkinsoncc on May 11, 2020 at 10:20 AM||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
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.
|Posted by wilkinsoncc on July 23, 2019 at 8:30 AM||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.
|Posted by wilkinsoncc on June 15, 2018 at 11:15 AM||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
|Posted by wilkinsoncc on May 29, 2018 at 8:40 AM||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
|Posted by wilkinsoncc on May 21, 2018 at 8:55 AM||comments (0)|
The Hackitt report was published last week and like many we were shocked at its conclusions, and importantly its lack of them in relation to cladding.
Given the clear case for action on combustible cladding and the ease with which an amendment could be made by issuing a corrigenda amendment to Approved Document B, we cannot understand why Dame Hackitt did not make this move a top priority.
As it stand there are no changes to the guidance in the Approved Documents and designers and contractors could continue to use Desk Top Studies to justify the use of untested cladding systems. This simply cannot be right.
We note that LABC have produced guidance saying they will continue to accept not only method 3 desktop studies but even method 4 studies subject to certain restrictions. This is all the more concerning as Dame Hackitt has suggested that only LABC should continue to approve High Rise buildings effectively banning Approved Inspectors working on them. This despite both Grenfell Tower and Lakanal House being Local Authority projects.
Over the next few weeks we will be making a series of posts reviewing the Hackitt report and setting out what we believe to be a better and more logical solution to the problems with the current system.
However in the meantime whilst we can continue to deal with High Rise Buildings (and in the longer term on buildings between 18m and 10 storeys) WCCL are today announcing the following policy.
1) We will advise clients to adopt the following strategy set out in BS 9991 2015 as though it supersedes the Approved Document - e.g.
• The external surfaces of walls should meet the provisions in Figure 17.
• In a building with a storey 18 m or more above ground level, any cladding material, insulation product, filler material (not including gaskets, sealants and similar), etc., used in the external wall construction should be of limited combustibility.
• Cavity barriers should be provided in accordance with Clause 19.
• External balconies that are enclosed should be constructed and separated from other enclosed balconies with compartmentation and fire-resisting construction in accordance with Annex D.
2) Where clients wish to use combustible construction despite our advice, then the external walls must meet the performance criteria given in BRE Report BR 135 for cladding systems. We will require full scale test data from BS 8414-1 or BS 8414-2 for the exact system to be used. We will not accept any variation from those test results and or desk top studies in any form to justify the use of combustible materials in systems that have not been tested.
We appreciate that this policy may result in losing projects to other BCB who do not take this approach and that this approach may be challenged by those producing combustible cladding products. However, pending the full outcome of the Grenfell Inquiry and revised updated guidance being issued by MHCLG we do not believe that it is appropriate to do nothing. We therefore call upon all BCB and those involved in construction to adopt the same consistent approach and to provide reassurance to those living and working in high rise buildings that cladding is safe.