TP Structures Ltd Articles & News

What are Building Regulations?

According to DirectGov: “The Building Regulations set standards for the design and construction of buildings, primarily to ensure the safety and health for people in or around those buildings, but also for energy conservation and access to and about buildings.”

Some buildings are exempt from Building Regulations, these include: Buildings used for the storage of explosives, or on a nuclear site, greenhouses and agricultural buildings, temporary buildings (as defined in the planning regulations), buildings on construction sites, mines and quarries, buildings with a floor area less than 30m2, nuclear fallout shelters and ”a detached building into which people do not normally go”

It can sometimes be argued that simple storage buildings fall into the category of  ”a detached building into which people do not normally go”, however you should always confirm with the Building Inspector that they agree with this categorisation before proceeding.  Buildings classified under any of these exempt categories are unlikely to be suitable for a different use in the future.

Most buildings are required to be designed and built in accordance with the Building Regulations and the Building Inspector will need to be assured that the building complies.  Normally, this means that you will need to provide structural calculations from a qualified engineer and we provide these as an inclusive part of our service. The inspector will also require proof that the building’s foundations are properly designed and adequate for their purpose – again, an engineer’s calculations will probably be required and we normally advise that a local engineer familiar with ground conditions in the area be used for this.

Exactly which regulations apply will depend on the use of the building. For instance, in the case of a heated building, energy loss calculations and even an air-test may be required.

Building inspectors may have discretion in how they apply the regulations – some regard them as general guidance only; others insist on them being applied scrupulously. You do not need to go to your local Building Control department for approval, another local authority’s department can provide the service, or you can use an independent ”approved inspector”.

Does my new building need planning permission? The straightforward answer almost certainly is ”yes”. There are a few exemptions to the planning rules such as permitted development for smaller buildings in some domestic situations, temporary buildings (which means buildings that are up for less than 28 days), buildings which are like-for-like replacements of existing buildings, and some types of agricultural building; however these exemptions do not apply to most new buildings. TP Structures can provide advice on applying for planning permission, as well as a planning application service at a very competitive cost.

There’s a bewildering choice of steel framed buildings to choose from. They all seem to meet your needs, but the prices vary so much. There’s a reason for this, and that is that not all buildings are created equal.

Things to consider when comparing different buildings and different building suppliers should include:

This list is by no means exhaustive but the answers can lead to substantial differences in costs between building systems as well as significant variances in quality. Ultimately the right choice should leave you with a building that meets all your long term requirements as well as complying with all relevant regulations and health and safety legislation.

Ever thought of working from home? How about an office in the garden?  The new ExpandaStudio provides a low cost solution

The ExpandaStudio requires only minimal foundations and is ideal for self assembly.

An assembly service is available in many parts of the UK.

For more details see http://tpstructures.co.uk/expandarange/garden_offices.htm

The size and shape of your building are determined by several factors. Foremost are the needs of your business. It may be that the height and width of the doorways are critical, it may be that there are minimum dimensions required by legislation (e.g. for MOT bays). In many cases the shape and size of the plot available will determine the building’s dimensions.

It is usually most cost-effective to minimise the span and eaves height of the building – increasing either of these has a disproportionate effect on the cost of the steel frame; equally buildings that are very tall and narrow will be expensive, as the wall area is large in relation lo the floor area. The most economical cost per square metre (floor area) is usually achieved by designing a rectangular building whose length is between 1.5 and 2 limes it’s width (span) and whose height is between 4m and 5.5m. Buildings which are oddly shaped (i.e. L-shaped or T-shaped) will incur significant extra cost. All buildings should be designed on a flat, level base.

The most cost-effective roof is symmetrical, with a central ridge. Offset ridges and monoslope designs again incur significant extra costs.

Most steel buildings are clad with profiled steel sheets, which are available in a range of colours and finishes. There are also architectural profiles and special finishes which are available at substantial extra cost. In general, standard box-profile cladding fitted vertically, is by far the most cost-effective option.

Where an insulated building is required, composite panels, which consist of a layer of insulating foam sandwiched between two steel skins, are normally used these days – in the past, a built-up system using mineral fibre between outer and inner steel sheets, separately applied, was used; however this type of system is less thermally efficient and is less common nowadays.

When a building is to be heated to domestic or commercial levels (i.e. where people are permanently at work in it) then it needs to comply with Part L2 of the Building Regulations. This requires the calculation of the CO2 emissions, thermal performance of the building fabric and services such as heating and lighting, airtightness, and efficient energy use. These calculations must be carried out by a suitably qualified competent person, and the building must demonstrate compliance with the required criteria in all these areas.

Because much of the information required to carry out the calculations (such as details of the heating and lighting systems) is not available at the time of designing a steel building, we are unable to demonstrate full compliance with Part L2. However, our design and specification is based on materials with the U values that meet or exceed the requirements of Table 4 of the Design Standards Section 1 of Part L2A. We also follow the guidelines of the leading manufacturers of insulated panels and fixing systems in specifying, detailing and installing materials and components to ensure that the required levels of thermal efficiency and airtightness are achieved.

Where insulation is required to deter condensation, or when the building is heated only to a low level, then a thinner composite panel can be used. These buildings are exempt from Part L2 as stated in this extract from the regulations:

From Part L2A of the of the Building Regulations, Page 12.

Buildings that are exempt from the requirements in Part L

16 Examples of buildings which are industrial sites and workshops with low energy demand include buildings or parts of buildings designed to be used separately whose purpose is to accommodate industrial activities in spaces where the air is not conditioned. Activities that would be covered include foundries, forging and other hot processes, chemical processes, food and drinks packaging, heavy engineering and storage and warehouses where, in each case, the air in the space is not fully heated or cooled. Whilst not fully heated or cooled these cases may have some local conditioning appliances such as plaque or air heaters or air conditioners to serve people at work stations or refuges dispersed and not separated from the industrial activities.

Provision of rooflights is determined and constrained by frame arrangement purlin spacing, solar gain and daylight factor, and normally equates to approximately 10% of floor area.

Rooflights can be single skin in the case of an un-insulated building or multi-layered to restrict heat loss where the building is to be insulated.  All rooflights these days  have to comply with fire resistance/combustibility regulations.  Rooflighs should also be of the  ’non-fragile’ type, designed to prevent anyone accidentally treading or falling on to them from falling through.

There may be occasions where windows are required. Windows will normally be double glazed, UPVC or aluminium framed, and can be provided with opening casements and accessories such as trickle vents.

Personnel doors are usually designed to be outward-opening and are usually made from steel for maximum durability and security. They are usually supplied primer-painted for customers to finish to their own requirements. Fire exit doors are of similar design and finish and are fitted with an internal panic latch or push pad but no external handle or lock. It is a requirement of Building Regulations that no part of the building should be more than 18m from a fire exit.

Combination doors are also available. These consist of a personnel door with external lock, together with an internal panic latch which overrides the locking mechanism, allowing people to escape from a fire, even if the door has been locked. These can be useful in smaller buildings, where access is restricted and it is not practical to provide separate personnel and fire exit doors.

Portal building kits are now available for self builds – spans up to 12m, and up to 5m eaves height. Fully galvanised lightweight steel frame. For full details see http://tpstructures.co.uk/industrial/portal_building_kits.htm

Roller shutter doors are the most popular and economic choice for goods doors. These will normally have galvanised laths and be hand operated by means of a chain. Options include electrical operation, coloured laths, Windlock guides and insulated laths, all of which incur additional cost. In general 0.6m (2ft) should be allowed above the door opening to allow space for the roller.

An alternative is the sectional overhead door, which uses hinged panels (with optional vision panels), these doors run on a track which protrudes into the building, usually horizontally, but which can be arranged to follow the internal roof line. Again, these can be both manually or electrically-operated.