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How to do a green home renovation. My energy-amazing house made the @ft, complete with photos! amp.ft.com/content/2b10c9…
So many wonderful commends in response to the @FT piece on our house! - Also, lots of questions, so I thought I would provide a bit more detail on the technologies we used. First, a caveat: we would not do the exact same things if we did the project today. But here goes... 1/many
Ours is an unlisted mid-Victorian terraced town house - built around 1860 - situated in the Bayswater Conservation Area of West London on the edge of Notting Hill. The 'hood has a rich architectural heritage and is achingly hip, as you would expect! 2/
The house is brick-built - basement, three middle floors and a mansard. Pitched east-west-facing roof. When we bought it, it had been tarted up by someone who clearly fancied themselves as an interior designer, but under all the slap it was in really bad shape. 3/ 
And I mean *really* bad shape. We had buckets out to catch the leaks. The wiring was so bad the lights would flicker and we had to disconnect most of it. Some of the radiator valves had been pumped full of silicon to stop them leaking. Wind howling through the window frames. 4/
We were spending £3300 on gas and electricity and half of the house was in the dark and we were not even warm! 5/
The house needed a virtual rebuild to make it suitable for 21st C living. Works included a glass in-fill and basement extension at the rear, rebuilt closet wing and stairs, an extra room under the garden, added bathrooms, new roof lights, moving most of the interior walls. 6/
So we thought hey, while doing all that, we really should go for world-leading energy performance! Can't be that hard, right? So, the story after that is well-told in the FT piece. Bottom line, the house works great and is incredibly comfortable, but getting there was painful. 7/
So here goes, the 12 technologies we went for, after a LOT of work and analysis. Spoiler alert. Some are interesting, some are very boring...
1. 90mm closed cell roof insulation by @Celotex. We opened up the roof space and got rid of the loft, so roof insulation was vital. 8/
1. 90mm closed cell roof insulation by @Celotex. We opened up the roof space and got rid of the loft, so roof insulation was vital. 8/
2. 75mm of closed cell underfloor insulation by @KingspanIns_UK in the basement. The house already had a basement, so we didn't have to one out (I'm sure our neighbours were disappointed). But we did deepen the one we had so we could make it warm and dry. So glad we did! 9/
3. External walls. We used 60mm @NBTltd #Pavadentro wood fibre insulation with NBT lime based plaster, applied to the inside face of the front and back walls. In a terraced house you don't have to do the side walls - the neighbours keep you warm (adiabatic boundary, innit) 10/
4. This is one of the boring ones. Efficiency performance is basically all about air-tightness. We made sure all joists and holes were sealed with Tescon Vana Tape by @ProClima. Word to the wise. You have to BE THERE while this is done. Or it probably won't be. 11/
5. Great windows. Basement & ground floor sliding doors, glass infill roof and sash windows by Folde. Low-performing conservation roof-light (as required by @CityWestminster) by @RoofLightCo, otherwise by @Velux and @Sunsquare_Ltd. Photos of sash windows before and after. 12/
6. Passive ventilation. Our top three floors are ventilated via the chimneys using @ventiveltd S PCHR passive pressure system with integrated heat exchangers, which really do the job! Bottom two floors (inc. kitchen, laundry room) mechanically ventilated (boo!) by @VentAxia. 13/
7. Two layers of Dupont Energain phase-change wall-boards. Aluminium-laminated panels contain a mix of a copolymer and a paraffin wax. Below 18 °C, the wax remains solid. Once the temperature reaches 22°C the paraffin wax melts, absorbing heat. Adds thermal mass. Lush! 14/
8. Rainwater capture. We didn't do this for economic reasons. With government subsidies, it would have had a 100-year payback. But we didn't get the subsidy because we only put it on the half of the roof that sloped to the garden, so the payback is 200 years. But classy, no? 15/
9. Super-efficient lights and appliances. LED fittings from @Orlight2 throughout. High-temperature water (and system back-up) provided by @WorcesterBosch Greenstar R1 system boiler. VX5 Home Voltage Optimiser Unit and 60Amp isolator, installed by @TreadlighterUK. etc, etc. 16/
10. Air source heat pump - 8.5 kW by Mitsubishi @meuk_les. This one has given us a lot of trouble. We think the plumber (who is not on our Christmas card list) let it fill up with all the crap that accumulates in a new heating system. 17/
11. Solar PV. 2.00 kWp system, designed and installed by @Treadlighter. Uses
11 Phonosolar Onyx PS250M-20/U all-black low-profile panels. Inverter and monitoring by @Enphase. Works exactly as planned - good job guys! 18/
11 Phonosolar Onyx PS250M-20/U all-black low-profile panels. Inverter and monitoring by @Enphase. Works exactly as planned - good job guys! 18/
12. Fuel Cell. 1.5kW natural gas Ceramic Fuel Cells Bluegen. They went into liquidation during the project, bought by @SOLIDpower_EN. Works a dream! 750l Akvaterm thermal storage tank. For the reasons why we went for the fuel cell, read this thread: 19/
So there you have it. If you are not a thermo/efficiency wonk, sorry to have cluttered up your TL. But if you are, I hope you enjoyed it! Per the @FT article, the house works great, payback on the funky stuff will be 25-30 years, some months our bills are zero. Selah. 20/20
