London EnerPHit rentals available soon

Grosvenor is completing three properties that achieve the EnerPHit Standard.  Available to rent, there will be two properties located in Belgravia on Passmore Street, with two bedrooms, and one three-bedroomed property in Mayfair on Adams Row. Grosvenor’s aim is to help its customers get more comfort and more health benefits from their central London homes. They believe EnerPHit properties provide tenants with more comfort, more clean air leading to better health, more peace due to sound insulation, and more control over your home’s environment.

 

Victoria Herring, Director  of Refurbishment and Retrofit at Grosvenor says the main challenge to build to EnerPHit standard was ensuring that additions were made in keeping with their context and character - typical London terraces with attractive brick frontage. This was done by the following:

• Implementing aerogel internal insulation that achieved low u-values on existing historic façade.
• External insulation was finished with brick slips to match existing rear façade exactly.
• Triple glazed mock sash windows were used in the front façade instead of the existing single glazed sashes; precedence permitted in City of Westminster.
• Passivhaus certified casement windows to the rear substitute inefficient metal Crittall windows;
• The retrofitting and refurbishment has also included efficient ventilation, and stringent airtightness.

Passmore is aiming for EnerPHit Certification via the heating demand route:

Passmore Street
Thermal Energy demand (≤25kWh/m2.yr)	23kWh/m2.yr
Thermal Energy load (≤10W/m2)	10W/m2
Primary Energy demand (≤130kWh/m2.yr)	125kWh/m2.yr
n50 (≤1ach@50pascals)	0.8 final test January 2015
Unit cost per m2	£2,400/m2
Wall	Front: 220mm Existing brick wall 20mm Parge coat 70mm Aerogel insulation 10mm Magnesium silicate board U-values: internally insulated 0.16	Rear: 20mm Brick slips 90mm Baumit EPS external insulation 220mm Existing brick wall 20mm Parge coat 53mm Kingspan insulated plasterboard U-values: externally insulated 0.11
Roof	120mm Kingspan rigid insulation 200mm timber joists filled with mineral wool insulation 13mm plasterboard U-value: 0.10
Floor	Extension: 150mm New concrete slab 165mm Xtratherm rigid insulation 65mm screed U-value: 0.16	Existing: 150mm Existing concrete slab 125mm Xtratherm rigid insulation 65mm screed U-value: 0.16

Due to the difficult form at Adams Row (including steep roof slopes), as well as minimum thickness insulation requirements, the component route towards EnerPhit Certification is aimed for.

Adams Row
Thermal Energy demand (≤25kWh/m2.yr)	N/A - 34kWh/m2.yr
Thermal Energy load (≤10W/m2)	N/A - 13W/m2
Primary Energy demand (≤130kWh/m2.yr)	129kWh/m2.yr
n50 (≤1ach@50pascals)	0.7 final test January 2015
Unit cost per m2	£1,320/m2
Wall	220-330mm existing brick wall 20mm Parge coat 70mm Aerogel insulation 10mm Magnesium silicate board U-values: internally insulated 0.20/ externally insulated 0.13
Roof	70mm Kingspan in existing 100mm timber rafters 50mm Kingspan insulation 53mm Kingspan insulated plasterboard U-values: 0.14
Floor	170mm EcoTherm rigid insulation 200mm existing timber joists 18mm plywood U-values: 0.13

Grosvenor’s aim is to refurbish around 3-5 units a year to EnerPhit Standard.  They plan to continually assess this target against customer demand. The fully furnished properties aim to be certified in January will be available to rent early 2015.

We are excited to be delivering five unique EnerPHit Passivhaus units with an 80% energy reduction for London’s Private Rental Sector. 

Victoria Herring, Director - Refurbishment and Retrofit at Grosvenor

 

Key Team:

Client: Grosvenor Architect & PH Consultants: Sturgis Carbon Profiling M&E: Edward Pearce  Structural Engineer: Hurst Pierce + Malcolm Contractor: Grangewood (Passmore) / Gaysha Ltd (Adams Row) Certifier: Co-Create Consulting

Further Information:

Grosvenor

21st January 2015

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