Passiv Studio
Garden studio / office in Lewes
Garden studio / office designed to Passivhaus principles
see blog
PassivOFFICE proves to be super comfortable!
Just had an email from my client at the PassivOFFICE:
‘Just thought you might like to know that on the coldest morning for 4 years (maybe longer), I am working in the garden office in a T-shirt, with no heating on!’
PassivOFFICE after 1 year
So Matthew has been working daily in the PassivOFFICE for over a year now and it’s been a real success – quiet, comfortable and obviously with no drafts! Colder days might mean switching on the 200W heater but if the sun comes out then it doesn’t even need this! The Lunos extractors with heat recovery are performing as predicted and are indeed whisper quiet. Unfortunately the vertical sliding shutter for solar control was not fitted due to cost but Matthew uses an awning in the summer months to control overheating. It demonstrates the Passivhaus logic on a small and simple scale.
PassivOFFICE – Slab
The Isoquick insulated raft is manufactured to the exact size required and clips together in a matter of minutes with an integral upstand eliminating cold bridges at this awkward floor / wall junction. The DPM is laid into the bowl and the reinforcement can be fitted and the slab simply poured tamping level with the top of the upstand. This photo shows the Isoquick in pink, the black DPM and the timber forms a slot in the slab for the sill of the sliding doors to provide a level threshold.
PassivOFFICE – Foundations
One of the advantages of an insulated raft foundation is that the site can simply be cleared and expensive and carbon intensive footings are not required
PassivOFFICE
This blog describes the construction of a small garden office for a client in Lewes designed to the Passivhaus standard. The building is a simple box and the footprint measures only 4m by 3.5m externally. One wall is formed of lift and slide doors orientated south-east, balancing the southerly solar gains with a pleasant aspect to the garden. There is a window to the south west to provide summertime secure nigh-time ventilation (in conjunction with the doors being lockable on trickle). A solar sail erected in the summer will control overheating. A pair of very quiet Lunos single room heat recovery extractors will provide high indoor air quality and reduce energy consumption. The floor is a 300mm Isoquick raft with integral upstands / kerb eliminating thermal bridges and providing a bowl into which the reinforced concrete slab is poured and tamped level with the top of the kerb. The slab will be polished as the final floor finish and provides thermal mass to regulate the internal temperature. Walls are timber I beams with pumped Warmcell clad in 100mm of woodfibre and timber rainscreen. The roof is PIR with a wild meadow green roof. Heating will be very minimal and is provided by an electric radiator. Although the Passivhaus logic has been applied, with U values around 0.10, PHPP modelling suggests a heat demand around 45 KWh/m2/year significantly above the 15 KWh/m2/year limit but the discrepancy is due to the high surface area to floor area inherent for a very small building and the minimal internal heat gains for this office (not having all the associated kit a house might contain).
