Building Regulations: Solid Wall | Insulation | Planning Portal
As well as revisions to Part L of the Building Regulations, the To meet Part L when constructing an extension you need to meet at least the following wall or roof construction to achieve these standards, in certain construction make-ups the. Section 3: Separating walls and associated flanking construction details. Separating . Part E of the Second Schedule to the Building Regulations , provides as follows: . Sound. required to meet the requirement of. Regulation. Registered Construction Details are a set of thermal details designed to minimise heat loss through weak points in the building envelope. This is vital to the.
Over recent years, we have seen the timber frame industry moving from 90mm to mm external wall studs. This provides additional space for installing insulation. Reflective breather membranes have also been introduced to effectively block infrared radiation, enhance the thermal performance of the airspace, and consequently increase the overall U-value of the construction.
Nobody wants thicker walls: Novel insulation products, reflective vapour control layers and air tight membranes all deliver better thermal performance. With the insulation and the timber structure of your typical timber frame house sharing the same sectional space within a wall, brick clad timber frame external walls' thickness can be kept below mm, while delivering U-values of 0.
Choose a cladding such as timber, brick slips, or render on battens instead of brickwork and external wall thickness can be reduced still further - along with the amount of embodied energy used.
- Building Regulations: Solid Wall
- The Building Sheriff's Guide to Having an Extension
The requirement to test the air permeability of new dwellings was a major change in Approved Document L The air that we warm up in our houses during the winter leaks out at an alarming rate. By reducing air permeability, we reduce the amount of warm air escaping, so reducing the volume of air we need to heat, reducing our fossil fuel bills and reducing CO2 emissions.
Building Regulations and Standards
Those countries which have championed the benefits of airtight buildings for many years also happen to be those which have championed timber frame for just as long. This is not a coincidence. Tried and tested techniques and details from overseas are now becoming commonplace in the UK. The polythene vapour control layer which is typically used in timber frame construction now fulfils a second important role in the UK, that of an air barrier.
Indeed, the Canadian R timber frame house system prides itself on achieving just 1. The UK construction industry has a lot to learn, although some manufacturers are rising to the zero carbon challenge. When air tightness levels below 5 changes an hour are anticipated, it is recommended that a mechanical ventilation heat recovery system MVHR is installed as part of the construction process. Warm air extracted from rooms such as kitchens and bathrooms is ducted through a heat exchanger, which collects the heat from outgoing air and uses it to heat fresh incoming air.
This allows plenty of fresh air for the building occupants and moist stale air is extracted at source. It takes less than Watts to run a system, considerably less than the heat energy it recovers. Well-insulated, airtight timber frame buildings work well in summer, keeping daytime heat out — as proved in certain areas of Canada and the US where summer temperatures are stifling. Unlike their traditional masonry equivalents, their lightweight structure does not absorb heat well, so it cannot contribute to the excessive and uncomfortable night time temperatures many people experienced this summer as masonry walls release their stored up daytime heat.
In winter, timber frame building's quick heating response time can be appreciated. Without a heavy energy absorbing internal structure to heat up first, occupants benefit from a fast heating response, on demand, while benefiting from low heating bills too.
A Guide to Cavity Walls, Brick/Block Work of a House Extension
The edition of Approved Document L will come into effect from 1 October For the first time, calculations for thermal bridges are required, or poor backstop values have to be assumed. Thermal bridging occurs in all construction types and is caused by areas of reduced insulation, or where an element passes through the insulation.Building Regulations
Thermal bridging increases space heating requirements by allowing heat to flow more easily through the thermal envelope. In winter, this creates low surface temperatures around the thermal bridge, leading to an increased risk of surface condensation.
Wood has a lower thermal resistance than the insulating materials placed between the framing members.
Therefore greater heat flow occurs through studs, plates, rails and joists than in other areas of the external wall or roof structures. This increase in thermal conductivity is referred to as thermal bridging. In general, thermal bridges can occur at any junction between building elements or where the building structure changes.
Many other building materials have lower thermal resistance than timber and could be significant factors in thermal performance.
For example, a steel post within a timber frame external wall would create a significant thermal bridge unless it was detailed not to bridge from the warm side to the cold side. As the brickwork and blockwork skins go up, your builder will tie them together at regular intervals to stop them moving independently of each other.
These ties are laid into the mortar beds. They should be stainless steel or galvanized, and they all come with a drip or twist in the middle to make sure the water, like Steve McQueen, can't get across to the other side.
Sheet insulation material will also start to arrive and your builder will place this into the cavity as the walls go up. There are a few different makes which can be used - Celotex, Kingspan, Jablite etc and they all perform the same function.
Achieving 'thermal comfort' in timber frame buildings
They are easy to cut and insert although cutting Jablite will make you look as if you have just wandered in from the set of Ice Station Zebra 2. The sheet insulation is clipped in position with imaginatively named sheet insulation clips to stop it falling or leaning over and bridging the cavity.
Above any openings for doors and windowsyour builder will place a lintel, and as your extension is going to be built in cavity work, he will, funnily enough, insert a cavity lintel.
There are many different designs and shapes of lintel, but a cavity lintel will have insulation inserted in it to prevent any cold spots on the inside wall which can lead to condensation problems.
He will place the lintel onto the block and brickwork either side of the opening with a minimum mm bearing so as to spread the load to either side of the opening. Where the cavity wall terminates at a door frame or window frame, the cavity must be closed and the brickie will do this in brick or blockwork, but he must incorporate a vertical damp course to prevent water penetration.
He may chose to use a special cavity closer - these tend to be a bit pricey for what they are, but for his part, they are quick and easy to use.