I built my two storey extension for 20% of builder's quotes

This site shows how - step by step from design to completion

Fitting UPVC Windows with Expanding Foam

The last thing I needed to do in order to be water-tight was fit some windows. Once that was done I could say I had completed the build of the extension.

I know there are many that freak at the idea of using anything other than wood to make windows for old houses. However, my criteria were:

High thermal efficiency

Attractive appearance that suited the building

Low or no maintenance (though I like building and making I am rubbish at maintenance)

Provided windows ticked all these boxes I was not a slave to any particular material. From years of experience I know that there comes a time when wood just does demand regular maintenance. After much deliberation and searching I installed UPVC windows in the main house a few years back. I have been very happy with the performance of these windows and had nothing but positive comments about how they look from neighbours. I researched who made the mouldings and decided to have new windows that were the same.

main house windowThis is one of the windows that was fitted into the front of the house several years back. I accept it is not identical to the lambs tongue Georgian  window that was taken out, but I believe it to be an attractive and acceptable compromise, baring in mind the advantages it brings.

The glazing bars are external, not those that are sandwiched within the glazed unit. It make is a little harder to clean the windows, but the appearance is much better.

 

 

main window insideWhen only one half of the window opens it is usual to have only one casement. However, this produces an asymmetry to the window because the non-casement side would have large panes of glass. I do not like this effect so insisted on two casements even though one side is fixed.

I also chose to not use UPVC sills as they look flimsy, are obviously plastic and did not suit. Instead I install a small stub sill beneath the window for drainage, but also fitted large concrete sills which I painted green.

On the inside the windows are coloured ivory, reducing the plastic appearance that you can get when they are bright white.

This picture shows the inside of the window. The surface mounted glazing bars, ivory colour and Ogee moulding all help to mimic the original window whilst minimising the plastic effect.

 

The windows seal perfectly and they have a very high thermal efficiency. In fact, with a U value of 1.7 the thermal efficiency of the windows exceeds that of the solid brick walls which will be around 2.

cavity closerI had built thermabate cavity closers in around the window openings.

If was probably unnecessary baring in mind the windows would all be foamed, but I chose to fill all the small gaps with PU foam to both help firmly hold the closers in place but mostly to be certain that there would be no way any draught could sneak its way around the window once it was fitted.

I measured the openings time and time again as I was paranoid of ordering windows that did not fit and could not be altered.

As a rule, the window should allow for a 5mm gap all the way round. This allows a little play to square up the window and squirt some foam in.

My fussy specification for the windows meant they were not cheap. In fact they are easily the most expensive thing to the build so far.

wrong windowI needed 12 windows in all, counting the large French doors.

I measured again.

I measured the openings time and time again as I was paranoid of ordering windows that did not fit and could not be altered.

As a rule, the window should allow for a 5mm gap all the way round. This allows a little play to square up the window and squirt some foam in.

My fussy specification for the windows meant they were not cheap. In fact they are easily the most expensive thing to the build so far.

I needed 12 windows in all, counting the large French doors.

I measured again.

 

 

small kitchen windowThe small kitchen window is a fixed frame with no casement, and being small was easy to handle, so it seemed a good place to start.

I was very relieved to find that it fitted very nicely.

I would deal with the arch trim later.

I fitted a section of bullnose trim to fill the arch space. I used white mastic all the way round to seal the window.

The standard hinges on just about all French doors these days are huge, chunky surface fitted affairs. We consider these to be ugly and unnecessary, so asked the manufacturer if he could find some traditional butt hinges.

They did find some. Like the surface hinges, they offer adjustment, just not as much. However, there is plenty provided the frame is installed accurately.

 

 

 

bullnoseWe think these are much neater.

The completed extension with all windows fitted. It was so nice for all the wind and rain and snow to stay on the outside and not come in to join us.

With the windows fitted I declared the extension shell complete. I still had a couple of week before my big birthday and Christmas, so decided to take the rest of December off.

 

 

 

 

hinge the extension