Achieving an airtight property requires a lot of care and attention to detail during building works but figures of 2-3m3/m2/hr@50P pressure are achievable without major expenditure as long as all gaps are filled as the works progress with the generous use of expanding foam and careful filling of all joints/service entry points etc.

Also, wet plastering is one of the best ways to ensure airtight masonry walls. Current regulations ask for a feeble target of 5. Timber frame houses use different methods to achieve air tightness including membrane’s and a lot of special sealing tape.

Installing cavity wall insulation ranks among the most efficient methods to minimize heat loss in existing buildings.

Homes built post-1920 often feature a gap between the exterior and interior walls. This design was initially intended to lessen dampness and provide better insulation than the single-layer walls that came before, yet there’s still room for enhancement.

Filling this cavity with insulating materials, such as polystyrene beads or mineral wool, can conserve up to 33% of the heat that would otherwise escape. The process is surprisingly straightforward.

The installation crew drills holes into the walls and pumps the insulating substance into the cavity. Despite sounding like a major undertaking, it’s actually quite simple and cost-effective, offering significant energy savings for less than £1,000.

In new-builds builing in a cavity of 150mm wide has become the norm. When filled with 145mm of a PIR based foam interlocking sheets from Celotex or Xtratherm can achieve excellent insulation values of 0.14U or less. Alternatively if you are going to clad or render your outside walls then External insulation provides the most effective form of insulation with 0.14 to 0.10U achievable.

Please see our downloadable guide for Self-builders for further information or just give us a ring for more detailed information.

When installing new floors or replacing existing internal solid floors, fitting 120mm to 180mm of Celotex or a similar PIR foam-based insulation is advisable. If the internal floors are suspended timber, you can insert the same material between the floor joists, sealing any voids with expanding foam. However, it’s crucial not to cover the air bricks, as doing so could lead to wet rot in the floor timbers.

This insulation approach is durable and significantly reduces heat loss, enhancing the comfort levels in your home.

Enhance your home’s energy efficiency by topping up existing or installing new glass fibre/Rockwool insulation, ideally encased in a plastic sleeve like the Knauf Space Blanket, to a depth of 300-400mm. Avoid the temptation of installing less than 300mm to 400mm on flat loft ceilings for a quicker, cheaper fix.

This investment is minimal and typically recoups its cost within 1-2 years. For spaces with an existing floor, lay the insulation over floorboards to maintain access and maximize insulation benefits. For storage areas, consider using pre-insulated floor panels available from builders’ merchants. Remember, compressing the insulation diminishes its effectiveness, so keep it fluffy and uncompressed for optimal performance.

In the UK, an astonishing 25-27% of our fresh water supply is used for activities like flushing toilets, laundry, showering, car washing, and garden watering. With the rising costs of gas and other fossil fuels, water prices are also climbing rapidly. Consequently, installing a rainwater recycling system is a sensible choice, both for environmental conservation and financial savings.

The installation process is straightforward during the construction of a new property or the refurbishment of an existing one. While the cost is relatively modest for builders, ground workers, or plumbers, it does necessitate setting up a new internal rainwater distribution pipework system. Such a system can halve your water bills, typically paying for itself within 4-5 years. Remember to inform your water company about the installation, as they may reduce your standing charges too.

When selecting windows for new homes or considering replacements, it’s crucial to invest wisely. Triple glazing options from brands like Ideal Combi, Velfac, Nordvest, Viking Windows, or The Green Building Store are available at approximately £550-650/m². These windows offer a durable solution, exceeding 30 years of use, and significantly reduce energy losses with U-values between 0.7 to 1.0 W/m²K or lower. Ensure you’re provided with whole window U-values rather than just mid-pane figures to get a true sense of their efficiency.

For those opting for double glazing, it’s important that the windows achieve whole window insulation values, aiming for a U-value of no more than 1.6. Be cautious of quotes focusing solely on the glazing’s U-value, which might seem appealing at 1.2U but doesn’t reflect the complete window’s performance. Request features like warm edge spacers, a 16mm argon-filled cavity, and a Pilkington Optitherm soft low-E coating or equivalent to enhance insulation.

In cases where original single glazed windows must be preserved due to heritage listing constraints, secondary glazing is a viable alternative. We recommend opting for double glazed secondary units, adhering to the same specifications recommended for double glazing, to achieve significant improvements in thermal efficiency.

When the exterior appearance of a building can be altered, or if the property already features a rendered finish, opting for an external insulated render system (e.g., K-Rend, Weatherby, Sto, Permarock, or Weber) offers the most significant reduction in heat loss. Given that such an upgrade is typically a one-time investment, it’s advisable to choose at least the minimum recommended specification without settling for lower quality. The incremental cost for thicker insulation options is relatively minor compared to the substantial benefits in energy savings they provide.

• Minimum Specification: Use 80mm of PIR insulation behind new plasterboard.
• Medium Specification: Opt for 100mm of PIR high-density foam/Celotex insulation .
• Super Insulation Specification: Choose 150mm of PIR based insulation.

External insulation significantly impacts a building’s heat retention by mitigating most structural cold bridging effects and substantially reducing air leakage heat losses.

For buildings where exterior modifications are possible or those already featuring a rendered finish, applying an external insulated render system (such as K-Rend, Weatherby, Stow, Permarock, or Weber) stands as the optimal choice for minimizing heat loss. Considering this type of renovation is typically a one-time event, investing in at least the minimum recommended specification is highly advisable. Opting for a lower specification to save costs upfront is not recommended, as the slight additional expense for thicker insulation options pays off substantially in terms of energy savings and heat retention.

• Minimum Specification: Incorporate 100mm of Polystyrene or Rockwool insulation, topped with a reinforced self-coloured acrylic render finish.
• Medium Specification: Utilize 100mm of PIR high-density foam or Celotex insulation with a reinforced self-coloured acrylic render finish, aiming for a target whole wall U-value of 0.18 W/m²K.
• Super Insulation Specification: Apply 200mm of Graphite polystyrene insulation with a reinforced self-coloured acrylic render finish, targeting a whole wall U-value of 0.14 W/m²K.

External insulation dramatically reduces a building’s heat loss by addressing most structural cold bridging effects and significantly improving air leakage heat losses, making it a crucial investment for enhancing energy efficiency and comfort.

Underfloor heating (UFH) is an exceptional choice for both new builds and homes undergoing significant renovations, offering energy savings and enhanced comfort levels. It eliminates the need for radiators, streamlining the aesthetic and functional aspects of home heating. Most plumbers can supply and install UFH systems, which are ideally suited for new insulated solid floors but can also be adapted for some timber floor structures. The installation costs of UFH are comparable to traditional radiator-based heating systems, with the added advantage of lower operating expenses.

UFH pairs exceptionally well with heat pump heating systems, enabling the heat pump to operate at reduced flow temperatures of 35-40°C, which is the range of highest efficiency. We’re here to guide you through the entire process, advising on the best UFH solutions for your home and how to optimally implement them for maximum comfort and efficiency.