Vertical sliders in timber frame

[akist]

Our dormers have 150mm timber frame fronts ( 6 x 2 ). I wanted to fit uPVC vertical sliders which are about 135mm. Looking at some photos of the exact same windows fitted on a 300mm cavity wall opening, they are screwed in place with metal brackets attached to the plastic frames. I attach a photo where you can see the metal brackets extending backwards and bolted into the concrete blocks.

It has now dawned on me that this method of fixing will not work on my 150mm timber frame and I presume that we cannot simply screw through the window frame (maybe it might interfere with the sliding action).

Has anyone got any suggestions?

 

[Deleted member 174758]

Am I reading this right? You'd like to remove the timber sashes from a vertical sash windows and replace with PVCu ones? Or are you going to replace the complete windows?

BTW, they aren't brackets, that is builders' band (cut to length) or window fixing brackets and the "bolts" are probably concrete screws with hex heads. The white plastic trapped under the bands is probably cavity closer strip

Sash windows (or at least traditional ones with sash weight boxes at the sides) cannot be fixed through the boxes, but why wouldn't strapping work in your case? After all it is attached (screwed) to the outsides of the windows before they are positioned in the holes

 

[akist]

Am I reading this right? You'd like to remove the timber sashes from a vertical sash windows and replace with PVCu ones? Or are you going to replace the complete windows?

No, not replacing anything. It is a new build, dormers are timber framed and their fronts are 150mm (cheeks are 100mm).

I want to install, brand new, uPVC vertical sliders, exactly like those on the photos. They come with those metal fixings you see on the photo, you twist the bracket and it locks into the grooves in the plastic frame, extending out backwards so you can bolt it into the concrete bolts.

What is "banding" ?

 

[Deleted member 174758]

I had a quick chat with a former colleague of mine who has a lot more experience of dealing with PVCu windows and he told me that, as far as he's aware, every PVCu profile supplier seems to have their own unique fixing clips, that they are all basically thin stamped galvanised sheet metal (like builders' banding) and that almost all the windows he orders comes with the straps tied up in a plastic bag, from the factory. He also gave me a supplier of a whole slew of different clips, called FrameFix. They also sell steel fixing bands (what I referred to as "builders' bands") for some windows. So it's a case of pick your manufacturer and make sure that they supply the appropriate fixing clips/bands/straps.

If you are fixing into timber you just use multifix screws or wood screws instead of concrete screws. The straps are thin enough to be bent round timber framing if needs be so, That's certainly what we have to do with timber sashes into some dormers and oriels as there is no other way to get a fix

 

[akist]

. The straps are thin enough to be bent round timber framing if needs be so,

That is exactly what I was told today speaking to a fitter, use the same straps but bend them . wrap them around the surrounding timbers.