- Written by Merry Albright
- Published: 23 June 2015
With the roof tiling complete and looking spectacular, we were able to start the window installation and tackle the interior first fix along with the detailed outer facings.
The installation of doors and windows made the house pretty much watertight in construction terms, which enables us to divide the scheduled work into two sets of 'critical path' trades (internal and external) running parallel to and largely independently of each other. This saves time on site, gives some flexibility with trades and releases us from the vagaries of the British weather.
We've chosen to use the Border Oak softwood windows throughout on this cottage as they are our most popular. However, in a crazy moment, we asked for them to be painted in a more daring dark green. We often recommend our lovely soft greeny/grey colour on our joinery, but thought this was the ideal opportunity to experiment and make a more contemporary statement. After endless test pots (of colours that were marginally distinguishable from one another) we decided upon this bespoke mossy tone, with a hint of ink and smoke (sounds fancy doesn't it!) hoping it would work well against the brick and render, but would also complement the glass and weatherboard. As it is very much a 'natural' colour, we felt it would work against the rural backdrop and changing seasons. It was a bit of a risk, but we thought it would be fun to try something new.
By using the same colour on the windows, doors and weatherboard we have been able to unify all the various parts of the cottage, but we have used different products to suit each application and base material. The product used to treat the weatherboard is a new OSMO product, which is half oil/half opaque paint and can be mixed to any paint reference. The only issue is that the bespoke colours are mixed in Germany so it can take two weeks or more to get it. Thinking we were being super efficient we chose to paint all the loose boards before they were fitted. This works well in theory, until you realise you have under ordered and run out of paint! So that the carpenters could carry on without delay, we decided that the boarding should be fitted and the remaining wood painted in situ. Next time we will order more paint than we think we need!
The exterior of the house is mainly rendered, which is now an iconic Border Oak finish that has been one of our most recognised trademarks since the original Pearmain Cottage appeared on Grand Designs in 2001. Under the outer render facing are layers of super modern and innovative construction details; devised by us to meet and exceed the ever changing regulations and help us deliver a house that is virtually airtight with minimal thermal bridging. The core structural material is Kingspan SIPs (we are one of their approved partners and one of the very first people to ever to use SIPs in the UK; so we have a very thorough specialist knowledge).
The SIPs work in partnership with the oak frame to provide overall structure - on this particular house there is also a section that is completely oak framed with our infill panels and glass inserts. The internal face of the SIPs is battened (to create a service void) and lined with a continuous high tech intelligent airtight vapour control membrane. This is taped and sealed at every conceivable point, before the interior plasterboard is fitted. The external face of the SIPs is battened (with a cavity), covered with a breathable membrane and overlaid with a continuous insulated carrier board before two coats of a specialist render and integrated mesh are applied. Obviously that is the slightly simplified version of what is involved - all the complicated junctions, details and 'break through points' are already designed and factored in by our technical design team before the house is built. Our aim is to deliver a house that is virtually airtight and super insulated, but not to the point where you are forced to consider swapping your heating system for a mechanical ventilation system! Our approach is to build houses that don't need either - passive in the truest sense.
Next……the internal features take shape.