MEMBRANES & BARRIERS
Radon Barrier: Similar to a Damp Proof Membrane but with an additional benefit of preventing the penetration of radon gases into the build. Radon is a naturally occurring radioactive gas which can potentially damage your health if concentrated under an unprotected floor slab.
Vapour Control Barrier: A layer used to minimise the moisture migration through an external wall, reducing he risk of condensation within the structure (interstitial condensation). This can also benefit the airtightness level of the build if installed and sealed correctly at all junctions.
Damp Proof Course (DPC): A horizontal barrier within a wall which is designed to resist moisture from rising through the structure by capillary action – known as ‘rising damp’.
Damp Proof Membrane (DPM): A layer of reinforced heavy gauge polythene used to prevent rising damp from bearing the ground floor construction.
Separation Membrane: A membrane laid between the floor screed and insulation which prevents cold bridging by ensuring that wet screed does not penetrate the joints in the insulation board.
Breathable Membrane: A breathable and vapour permeable membrane placed over the roof in order to waterproof the structure.
Air Tightness Membrane: Membrane and tape applied to windows, doors and junctions. Common weak points in a building’s fabric include the junctions between floors, walls and roofs. These need to be address by ensuring airtightness and to reduce thermal bridging.
Proprietary Insulated Vertical DPC Cavity Closers: A strip of insulation with a factory bonded ridged Damp Proof Course (DPC) used for window and door jams.
EFFICIENCY & INSULATION
Renewable Energy: Naturally replenished energy resources which will never exhaust e.g. wind and sun.
Finite Resources: Energy resources which are becoming increasingly scarce e.g. oil and natural gas.
U-Value: The measure of the rate of heat loss through a structure per metre squared per degree of temperature difference. The lower the U-Value, the lower the heat loss.
Thermal Conductivity: The rate at which heat travels through 1m thickness of material with a surface area of 1m2 at 1o temperature difference. The lower the thermal conductivity, the higher the thermal performance of the material.
PIR Insulation: A short term for polyisocyanurate; one of the most thermally efficient forms of insulation, used within our closed panel timber frame systems. In comparison with other insulating materials such as mineral wool and polystyrene ridged foam; PIR provides a superior insulating value.
Spray Foam: A type of insulation that is sprayed on site rather than cut as with PIR board insulation or packed as with wool insulation. Spray foam can be either open or closed cell depending on the requirements.
Closed Cell: A form of insulation which can resist both water and moisture and can defy air movement meaning that it will not slump or sag. Rigid phenolic or polyisocyanurate are two forms of closed cell insulation.
Open Cell: A form of insulation with foam cells that are intentionally left open; making the foam softer and more flexible for specific uses.
OTHER BUILD TERMS
Passive House:
- Improved insulation
- No air leakages
- No thermal bridges
- Highly energy efficient windows
- Orientation and shading to take strategic advantage of heating and cooling
- Heat recovery ventilation to moderate heating and cooling
- Increased energy efficiency by up to 90% resulting in lower heating bills
Airtightness: The prevention of air leaking in or out of the building envelope. An airtight build structure such as a timber frame home results in lower heating bills due to fewer draughts.
Carbon Footprint: The total amount of CO2 (carbon dioxide) produced and emitted, directly and indirectly by way of manufacture. Timber frame is not just carbon neutral, timber is carbon negative.
Thermal Bridging: Approx. 30% of the heat loss in a well-insulated building occurs when materials of poor thermal insulting value come into contact, allowing heat to escape through them. A well-designed timber frame home minimises thermal bridging and may eliminate it altogether.
BER (Building Energy Rating): BER is an indicator of a building’s energy performance in terms of hot water heating, ventilation and lighting depending on it’s occupancy. The scale ranges from A to G, with A-rated homes being the most energy efficient and therefore offering the lowest heating bills. A timber frame home is the most financially and environmentally sound way of achieving the lowest possible BER rating for your home.
