Bowed or Compass Sash Window Frames, Windows and Cills/ Sills Repaired and Restored in Brighton, East Sussex
When it comes to really showing you what we can do then you can look no further than this page. Bowed/ compass sash windows are one of the hardest windows to make from new and to restore them properly. These were originally made so that the owner could get a better view of the sea or surrounding area. These sought-after windows are not that practical anymore because you are very limited to what you can put within them. Therefore, you would only see these on Regency and early Victorian properties around the 18th century in England.
This is one of the most difficult windows to build because to construct a bowed sash window like this you need to set up jigs. This would make sure that the window is going to be square and has the right curvature on the sash.
We can guarantee that if we must take your windows away (depending on size) to our workshop facility. That we would have your windows back within 3 days and glazed as well. depending whether we are installing the original bowed glass and it does not have to be made.
Bowed windows sometimes get altered over the years
Another problem with old properties is that repairs can be botched through owners attempting D.I.Y attempts. Maybe carpenters/painters trying to make an easy fix through the years. Mainly the thing that does get damaged from the windows moving, due to the weather, water ingress and rotting timber and decorators is the glass.
The original glass would have been cylinder/ crown glass we have a dedicated page on this . Cylinder glass has a vertical wave effect in the glass due to being hand blown and swung in pits. This is then heated on a curved template to make the curved glass we can still obtain this from 3 different sources in Europe direct from the manufacturers. Please see our dedicated page on this to find out more about Cylinder/ Crown glass Architectural glass for more info.
Unfortunately, most of the glass that you will find in these curved windows will have been replaced with float glass. altering the aesthetic look of the property and the sashes completely. The only way to install float glass is to cut the back of the windows on the sight line. The curve on the window where the moulding is will be cut away. This is a very frowned upon thing with the councils or conservation officers in listed properties. Because you are altering the total look and way they were made on the windows themselves. It’s a preference that some people take because of the cost of the glass itself. We can install the original bowed glass in plane float glass at a much cheaper cost and a quicker time scale than the original cylinder glass.
Why are Bowed sash windows one of the hardest windows to make
Essentially, this is because the glazing bars must be in line with each other. Sometimes within time the windows will have moved, and the window frames themselves will be totally out of square. The windows could be different throughout the house due to different carpenters making them when they were originally constructed. Maybe upgrades as rot may have got hold of certain windows and people do not know how to restore them.
So you have to have templates made from every window that you have just in case. When you have a mid-rail and it is slightly different from the original then the overall width. This will make it smaller or larger if the curvature is different and the window will not fit. This can be explained if you split an oval shape down the middle at the longest points. Then If you squashed the curve it would be completely different curve and the diameter would be totally different.
Repairing curved windows and why curved window are made in sections
To get the curve either on the windows or the windowsills themselves you must use glulam timber. Glulam timber has been joined by glue and clamped together; this is then cut on a bandsaw to get the curvature of the windows themselves. Or modern-day standards you would use a baring guided spindle moulder blade and a template.
On this project page you can see me cutting the sills into the windows in sections. This had to be done like this because the windows are being restored and the curvature of the window is a very tight curve this was more like a semi-circle with a diameter of 2ft.
If the windows were made in one piece than the likelihood of the windows having defects would be high. The strength of the timber would be compromised due to the grain being back to front instead of side to side. This will always cause rot as well because the water will soak up through the end grain and empty cells. When this is done you always make a subsill as well going around the main sill so that is protected from the elements.
repairing the stile of the window.
This is a method that we use, it’s called a splice joint that will create an extension to the stile. Stiles are notorious for going rotten. This is again because of the end grain being at the bottom of the sash. Especially where the water lies quite often due to rain or condensation. City and Guilds looked at this and have introduced us into their new curriculum for advanced architectural joinery.
The stile can be extended in this way because all the pressure is going through the timber in all angles creating equal force. This should be glued, and 2 dowels inserted at an angle to lock it of completely. With this we would run tit through a router or a spindle moulder depending if you have the mould. Then we would mortice the bottom extension and insert it back into the bottom rail creating a restored window.
I hope you have enjoyed one of our many project pages.
If you are thinking about restoring your sash windows than take two minutes to look at our Antique sash window furniture shop to give your property that original traditional look. We cover the following areas: Brighton and Hove, Lewes, Hassocks, Haywards Heath, Burgess Hill, Crawley, Gatwick, Uckfield, Seaford, Cuckfield, Eastbourne, Pevensey, Hastings, Shoreham, Horsham, Worthing Pulborough, Chichester, Arundel, East Sussex and West Sussex
