Steel and slab

Still with the boring stuff, unless you're an engineer! Here we have photographs of the steel, one interesting point here is we couldn't change the thickness of the raft so where the party is located you can see that  we have added additional steel.

Concrete is pumped in to produce a fairly shallow raft of 200mm thick. Note the ground was backfilled up against the block to provide support to the insulation, this also provides protection against frost heave. Having a shallow foundation increases the possibility that the ground could freeze below the sub foundation insulation, in severe weather conditions. The concrete wall will provide protection against frost heave as well as acting as a permanent shutter for the raft.

Foundations

This pair of Passive Houses will have a sub foundation insulation; A standard method used in Germany but one of the first times it has been used in the UK.

The topsoil is scrapped away and a shallow trench is dug for a small retaining wall.

Before the sub foundation insulation is placed a dwarf retaining wall is built

This is not load bearing but is purely to support the insulation 

600mm of Extruded polystyrene with a density of 45Kg/M3 and a thermal conductivity of 0.032W/(m.K) is placed around the perimeter of the wall.

The hardcore is then sand blinded to produce a flat level base ready to receive the insulation.

Slabs of insulation are then placed carefully over the expanse of the foundation

 

The foundation insulation is then increased in thickness laid over previous layers crossing the junctions of the preceding layer to improve the load bearing capacity. A total thickness of 300mm is finally placed

Finally an impervious membrane is laid over the polystyrene which acts as a gas barrier and protects the insulation from damage when the concrete is poured

Who What When Why

Low Carbon Construction is attempting to build a pair of semi-detached houses for the social / affordable housing sector constructed from solid wall masonry and will be certified as a Passive House.

The site owner is Blythe House Lettings Ltd and this project is part of an overall scheme of 8 units which are all being built by the main contractor - Low Carbon Construction Ltd. Clan Products NW will supply the the materials to enable Low Carbon Construction the build a Passive House shell through their company Thin Joint Technology. Toby Rollason from Lune Architects have adapted a previously consented planning permission for the pair of semi's to ensure they meet PassivHaus standard and are working with the Scottish Passive House Centre (SPHC), who will monitor the project and ultimately provide accreditation.

A Passive House must achieve a number of defined targets, 

1) the heating demand must be less than 15 KWH/M2 per year and that the total energy demand for heating, hot water and domestic appliances should be no more than 42 KWH/M2.

2) The air changes must b less than 1m3/(h.m2)@50Pa

3) The windows (frame and glazing) should be less than 0.8W/m2K - triple glazed

The owners and workforce of Low Carbon Construction Ltd have many years experience using modern methods of construction and producing very high quality builds to exacting standards. This will be their first certified PassivHaus build and with a tight budget based on standard build costs, the objective is to prove that PassivHaus can be a cost effective solution to provide low cost and affordable housing. In this difficult economic climate Low Carbon Construction Ltd believe they can replicate the quality assurance of certified PassivHaus units across the social housing sector at a cost comparable to traditional build. With energy costs set to rise astronomically over the coming years Low Carbon Construction Ltd believe they can be instrumental in addressing fuel poverty.

First Days

Welcome to the Blogspot for the No Mans Heath Passive House

This blog has been posted to keep up to date with the build of a pair of semi detached houses which will be built to the Passiv Haus principles and certified by the Passiv Haus Inst Germany.
This will be the first semi-detached to be built for a RSL and certified by the Passiv Haus Institute.
We intend to provide you with a weekly update of how the build progresses and what problems have to be overcome during the course of the build.
Fortunately Low Carbon Construction are well versed in using modern building materials but this build will introduce some new products to create a Super Insulated Masonry house.

Chris Hirst Director of Thin Joint Technology Ltd