The Building Regulations and Approved Documents contain a considerable amount of guidance. Using our considerable experience and to help you with common technical issues and interpretations, the following questions and answers are intended to provide guidance and potential solutions for achieving compliance with the Building Regulations.
These questions and answers apply to the current Building Regulations. They are not prescriptive answers and it is important to remember that each situation is different, so answers cannot always apply to all situations.
If an NHBC Buildmark Warranty is being provided for your project, there may be additional requirements to consider, which are in addition to the requirements of the Building Regulations. Further guidance on NHBC Standards can be sought from NHBC Standards and Technical.
The Q & As are split into Regulation procedures and categories.
There are many classes / scenarios to consider when deciding which types of buildings fall into which class.
Read our guidance note to help you decide.
When an Approved Document makes reference to a named standard (listed in the appendix of the Approved Document), this is the relevant document to use. However, if this version of the standard has been revised or updated by the issuing standards body, the new version may be used as a source of guidance provided it continues to address the relevant requirements of the Regulations.
Volume 2 of Approved Document B currently refers to the guidance in several of the BS5588 series of standards as a means of showing compliance with the requirements of Part B (Fire safety) of Schedule 1 to the Building Regulations. Until such time as the Approved Document is amended, these references remain part of the guidance approved under section 6 of the 1984 Building Act. As such, compliance with the guidance referred to would confer a legal presumption of conformity with the relevant requirements of Part B. Following any other guidance would not confer that legal presumption.
Where designers choose to follow the relevant guidance in BS9999 they will need to satisfy themselves and the relevant authorities that this guidance adequately addresses the requirements of Part B. It is strongly recommended in such cases that designers discuss their proposals with NHBC before starting work.
No. This may differ, however, if the house has inner rooms.
If the metal framed suspended ceilings are erected and lined with plasterboard prior to the construction of the internal partitions, consideration would need to be given to the prevention of the fire spreading within the void and over the partitions enclosing the protected entrance halls.
The installation of 30 minutes cavity barriers positioned vertically in line with partitions surrounding the protected entrance halls. Or a 30 minute horizontal cavity barrier installed throughout the whole of the flat compartment. Considerations should be given to the recessed lights that are fitted with hoods and extract duct penetrations should be suitably fire dampened.
The three traditional approaches to providing ventilation to car parks, taken from Approved Document B - Fire Safety, are:
The first point to make is that there are no direct equivalences between the Euro classes and the British classes. The reason for this is simply that the British and European tests measure different things. That does not make them necessarily a better or worse material.
Use the following table as a guide:
The above is only a guide and it really depends on the material. To get a European classification you have to do a European test and for a British classification, a British test.
If there is no change of use or structural alteration and the situation regarding fire protection is no worse than it was before, then building regulations do not apply here as they are not generally applied retrospectively. Therefore Building Control should not require you to upgrade the fire resistance to the beams.
However if the building is a workplace the client or tenant must carry out a Fire Risk Assessment and this should include structural fire protection issues if visibly found to be defective and where reasonably easy to improve matters. In this case therefore the client/ tenant should include for 1 hour fire resistance to be added (for buildings up to 18m in height).
Fire Certificates are no longer required for workplaces as theFire Precautions Act 1971legislation has been withdrawn. The current legislation is the Regulatory Reform (Fire Safety) Order 2005,sometimes called theFire Safety Order or RRO, which came into force in October 2006.
This requires that a Fire Risk Assessment is carried out for all workplaces and where there are more than five employees this must be a written assessment.
In addition the legislation also applies to the common parts of blocks of flats for the first time. The person occupying the premises should carry out the risk assessment, or employ a competent person to do so. For complex or multi-occupied buildings a landlord may have to provide a complementary risk assessment for common parts.
Assuming that the property was a shop prior to carrying out the works, for Building Regulation purposes the works fall under the category of 'material alteration'. As such,the fire precaution measures to the existing parts of the development should be as good after the works as they were before, and any newly constructed or modified areas should meet the current recommendations of Approved Document B. However, the premises also fall under the requirements of the Regulatory Reform (Fire Safety) Order 2005 and under this legislation, a suitable fire risk assessment and evacuation strategy must also be carried out and managed by a competent person. Whilst not always the case, it is generally accepted that the works necessary to satisfy both sets of legislation will include the following:
From a turning circle position or site entrance a further 20m driveway distance is permissible, from which point the 45m hose distance is measured. If the driveway continues beyond 20m from turning circle position or site entrance, then the turning circle should be moved to a maximum of 20m from the end of the driveway.
A fire service appliance should be able to park within 18m of a dry (or wet) riser inlet, and be able to clearly see the inlet position.
Requirement B1 requires 'appropriate provisions for early warning of fire'. Due to the high degree of compartmentation in residential developments the fire safety approach in Part B assumes only the occupants of the flat where the fire starts will initially evacuate. The occupants of other flats will remain in place and will only evacuate if the fire brigade consider it necessary after their arrival. There is therefore no need for an alarm system to notify all residents of a fire and there is generally no need for a fire detection system in the common areas of blocks of flats.
There may however be a need for detection in common areas to activate fire protection systems, such as automatic opening vents and fire doors on hold open devices, but these detectors should not be connected to alarm sounders.
Communal alarm systems may be appropriate where the building contains sheltered housing and centralised management controls are in place.
The following factors can be considered when deciding if a hallway is a habitable room:
The provision of a storage space within the loft area is acceptable, however the provision of an additional floor level, to be potentially used as habitable accommodation should not be considered without providing adequate means of escape. The following factors should be considered when assessing a storage space:
Definitive guidelines cannot be provided, but the important factor is to ensure that if the loft space can be readily and easily adapted to provide habitable accommodation, then further details and assessment will be required.
A step proposed as a remedial solution should only be considered if it can be reasonably considered to be part of the permanent structure of the floor. This would be a matter of judgement in each case but an isolated step on a plain wall adjacent a window is unlikely to be acceptable.
Where escape windows are installed with the bottom of the opening greater than 1100mm above floor level, the provision of a protected escape route would be acceptable.
No, thermoplastic insulation materials should not be used in this situation, as referenced in Diagram 11 and Diagram 30 of Approved Document B:2006 Vol. 2. The reason for this restriction is that thermoplastic insulation materials have a tendency to melt and the resulting voids can provide a route for fire spread over or through the line of compartmentation.
Thermo-set insultation, such as Polyurethane (PUR), Polyisocyanurate (PIR) and Phenolic foam, whilst technically classed as combustible, is acceptable as they tend to exhibit charring behaviour when exposed to fire, and so are acceptable and permitted to cross the line of compartmentation.
Providing the roof covering can achieve the external fire rating of AA, AB or AC, thermo-set insulation products are acceptable with adequate fire stopping to ensure the potential for fire spread over or around the insulation is restricted.
Refuges for disabled people are not required in car parks (basement or otherwise) serving residential premises. If the car park was open to members of the public and serves other non-residential uses, then this principle may change, and the guidance of BS5588-8 and BS9999 should be considered.
There is a lot of supporting information to consider any alternative, although it would be difficult to prove an acceptable alternative solution.
Increasing fire resistance of compartmentation could be considered, but sprinklers are also beneficial to life safety and fire fighting provisions, so whilst an increase in compartmentation will contain the fire within a specific area it will not control the fire temperature. Without sprinklers containment may be compromised.
A fully fire engineered design may be able to present an alternative solution, but it would be difficult to prove compliance with Building Regulations.
This is a requirement under Approved Document Part C Building Regulations. The Regulations provides an obligation to inform builders at the earliest stage if Radon is found on a site as this may affect the ability to achieve mortgages on properties.
Depressurisation/ventilation should be provided below the level of the radon barrier. Where the radon barrier is installed below the ventilation air space under a suspended concrete floor, a radon sump will be needed below the radon barrier to provide provision for this (see below).
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The purpose of this Requirement is to protect residents from noise produced in reverberant common areas. The Requirement only applies to "corridors, stairwells, hallways, and entrance halls which give access to the flat or room for residential purposes". To comply with this, it is recommended that absorbent treatment should normally be applied only to common areas onto which dwellings open directly.
Where separating walls, without doors or windows, are adjacent to common areas it would not normally be necessary to treat the common areas, assuming normal usage. Other situations are dealt with in paragraph 0.8 of Approved Document E (2003).
This means that reverberation measures (e.g. acoustic ceiling tiles) are only required in areas that lead directly to flat entrance doors e.g. common corridors/lobbies and not staircases in most flats,BUT reverberation measures in the staircase where the flats are accessed directly from the stair, such as small single stair flats.
Pre-completion testing or Robust Details.
For pre-completion testing, the solution would include:
Robust Details approach:
The guidance within the Building Regulations is that all toilets and cloakrooms should be provided with 6 litres / second of purge ventilation. Under Table 1.2a of Approved Document F1, the ventilation can be provided by purge ventilation with an opening window equal to 1/20th of the floor area. This would only be acceptable where security is not a risk. It is assumed that security is only a risk where the window serves a toilet or cloakroom on a level that is accessible from the outside
No. The requirement is that you achieve the mains water supply is providing no more than 125 litres per day per head. However, the inclusion of a grey water system could be used to offset the 125 litres / day / person requirement.
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Measured from the balcony floor level, the minimum requirement is 1100mm.
Yes, an 800mm guard height should be maintained above a parapet, and the design should not be climbable.
The wire mesh should not propose a foothold. Therefore for designs incorporating parallel wires in both directions, a maximum gap of maximum 35mm is required. Please refer to the diagrams below for guidance on different mesh designs.
You will find this on the NHBC Energy Rating service
Currently NHBC can accept Thinsulex, or a suitably British Board of Agrement certified product.
In recognition of recent changes to EU regulation, which relates to the phasing out of traditional, inefficient and high energy use light bulbs, the guidance concerning 'internal lighting' in the Domestic Building Services Compliance Guide, which supports Part L 2010, has been amended. The 2010 guidance now permits either:
Where standard fittings fitted with low energy bulbs are provided, this will satisfy the requirements of Part L 2010. In recognition of the phasing out of traditional high energy light bulbs, the above criteria for internal lighting may also be applied to sites being developed under Part L 2006.
Where low energy bulbs are not being provided, it will be necessary to show compliance by providing low energy fittings which only accept low energy light bulbs.
For all developments, where standard light fittings are used, the low energy bulbs must be installed on site in order for Building Control to be satisfied as to compliance.
Where the gradient exceeds 1 in 15, or where there are planning constraints, steps can be considered. Steps must be designed to meet the needs of disabled people. There should be a clear landing of 900mm at the top and bottom of the stair, a suitable handrail should be provided to one side of the steps where the flight comprises three or more risers, and step profiles should be designed to avoid tripping hazards.
In principle, the provision of a lift for multi-level new buildings should be the starting point for any design. However, there are situations where alternative arrangements can be considered to provide 'reasonable provision'. For example:
This work is a 'material alteration' and is controllable by building regulations so an application is required.
Part M will apply in all regards, so door widths, opening forces and a level threshold should be provided to meet Part M unless unreasonable to do so, in which case the access statement could be used to justify departure. Remember the DDA will still apply to buildings where goods or services are provided so this may be a good time to make improvements where reasonable to do so.
What is 'reasonable' depends on the merits of each individual case, including the scope and scale of the premises and takes into consideration the amount of building work, financial costs involved, and the benefits in in carrying out an alteration to provide compliance with a particular regulation. Where the building or element may be newly constructed then most work is reasonable, whereas for existing buildings or those which are listed or historic then this may affect what is reasonable.Building Control should use professional skill and judgement, including common sense, when arriving at decisions whilst striving to maximise compliance in line with the regulations.
The glazing to be replaced will be such that it is located within a Critical location- those areas being located as
a) between finished floor level and 800mm above that level in internal and external walls and partitions
b) between finished floor level and 1500mm above that level in a door or in a side panel, close to the edge of the door (ie within 300mm of the edge of the door)
The glass to be installed within the above areas should
i) break safely if it breaks( be glass specified to meet British standard 6206: 1981- Specification for impact performance requirements for flat safety glass and safety plastics for use in buildings)
In terms of safe breakage, a glazing material suitable for installation in a critical location would satisfy the requirements of Class C of BS6206 or installed in a door or in a door side panel and has a pane width of 900mm the requirements of Class B of the same standard
ii) Be robust- some glass gain strength through thickness- annealed glass, poly carbonates and glass blocks are inherently strong - Some annealed galls is considered suitable for use in large areas
iii) be permanently protected- if glass , in a critical location is installed behind a permanent screen- the screen should:
prevent a sphere of 75mm from coming into contact with the glazing; be robust and if intended to protect glazing that forms part of protection from falling, be difficult to climb
Note- the glazing in a critical location which is afforded permanent protection, does not itself need to meet the requirements of items i-iii above.
Where glazing is installed in critical locations in which people are moving in or about the building and might not be aware of presence of glazing then suitable marking or manifestation should be provided to the glazed section.
This manifestation should can take the form of various markings on the glass (eg stickers, etching, features) and some examples are- broken or solid lines, patterns and company logos- Permanent manifestation of large areas of glazing is only required when other means of indicating the presence of glazing are NOT used (these other means may include mullions, transoms, door framing or large pull or push handles)
To houses and flats-including common parts but not lifts, non residential buildings that share a power source with a dwelling i.e shop with flat over, conversion, extensions and alterations, land associated with a building ie fixed garden lighting, pond pumps, sheds, garage and green houses.
When the work is limited to replacement sockets and switches.
The works within the bathroom are within a special location the new outdoor wiring to the garage is new and the new circuit to the bedroom would under the guidance to meet Part P be classed as notifiable works under the requirements of Part P1 of the Building Regulations 2000 and a formal application to the local authority building control or private approved inspector building control body to carry out these works would be required.
The above works are to be carried out by a competent person or installer:
If that person or installer is registered with a Competent Person Scheme they are qualified to carry out specific types of work in accordance with Building Regulations and will deal with Building control issue with a certificate on completion of the work which can be used as proof for a Home Information Pack (HIP)
If you do not use an installer registered with a Competent Person Scheme then you will have to submit a building notice or full plans application and pay a fee to have Building control body come and inspect the work you have carried out.