Thursday, 26 April 2012

Clearing The Air

Through design and construction we have ensured that our building has plenty of highly efficient insulation in order to greatly reduce the amount of heat lost through the fabric of the    building, however, the effectiveness of our ‘thermal envelope’, also relies on the building being airtight, therefore steps are taken to seal any areas where air leakage may occur, some of which are highlighted below.

Above:Polyurethane expanding  foam has been applied to seal around posi-joists at each end. 
 Below: Sealant has been applied around insulation at window and door reveals, and to full depth
               around each frame. The excess foam will later be trimmed flush before  rendering.

Of course an air tight building will very quickly become a ‘sick’ building unless adequate air circulation and ventilation is provided. We can immediately see conflicting requirements, on one hand we have the need to prevent heat from escaping, and on the other a building and occupants that we must keep healthy by preventing the build up of moisture and stale air. In short, we need to keep the heat in, the moisture out and provide fresh air for everyone inside to breathe. In order to achieve all the above requirements and tick this seemingly contradictory set of boxes, our clients new home will have an MVHR system designed and installed. MVHR stands for  Mechanical Ventilation and Heat Recovery, this will allow the building to be properly ventilated with very little loss of heat.

The first roof trusses arrive on site.

The roof trusses are craned into position.

The diminishing truss set is put in place.

The roof trusses are braced and tied as the gable walls are completed.

The main structure is ready for rendering and the roof ready to be covered and tiled.