Having Problems With Fixings For New UPVC Windows

[Whitespirit66]

I'm helping someone fit a few DG UPVC window units into standard brickwork. We've used two types of fixings to fix the units in, without consistant success.

First we tried some concrete screws - the sort that are supposed to go into masonary without plugs, etc. Sometimes they do up tight, others they just turn but never tighten up.

Also tried some frame fixings, which are unbranded and came from Toolstation - I think. Anyway, we used the right length ones fpr the depth of frames (100mm anchors) and drilled the correct 8mm holes in frame and masonary. They were a little tight going through, so we knocked them through with a hammer. I think that's the correct way? Anyway, first window with these fixing, and although the fixings are all the way in, the screws just keep turning without tightening.

So, which are the best fixings to use, and what are we doing wrong?

Thanks for any help.

 

[Burnerman]

Depending on the type of fixing you have used......the 'proper' type for upvc have a threaded nut in the end which when tightened causes the plug to expand into the brickwork - somewhat like a long traditional rawl bolt, in fact.
If you hammer them in, sometimes this nut pops off so there's nothing for the screw to bite into.
Personally I prefer 10mm gear for frames but thats just me!
John

 

[s60tsy]

what size drill bit did you use for the concrete screws?

 

[Whitespirit66]

Thanks John.

Yes, the frame fixings from Toolstation are the ones with a long screw in a plastic tube, with a small plastic piece on the end. This piece should get drawn inside the tube to make it expand as the screw turns.

Wasn't sure how to push them in without hammering, as they seemed a bit tight going into the brick Could have drilled a slightly bigger diameter hole than specified, but was worried that this would cause other problems.

Do you prefer a certain make or brand?

 

[Whitespirit66]

what size drill bit did you use for the concrete screws?

Not really sure, as I didn't drill the holes for these. Around 8 or 10mm I would guess. I'm sure the friend I was helping would have used the hole specified on the packet. He's got a good range of SDS bits.

 

[s60tsy]

6-6.5mm should be used for concrete screws, if the hole is too big the screws wont bite

 

[Burnerman]

Thanks John.

Yes, the frame fixings from Toolstation are the ones with a long screw in a plastic tube, with a small plastic piece on the end. This piece should get drawn inside the tube to make it expand as the screw turns.

Wasn't sure how to push them in without hammering, as they seemed a bit tight going into the brick Could have drilled a slightly bigger diameter hole than specified, but was worried that this would cause other problems.

Do you prefer a certain make or brand?

I like to go for Fischer stuff when I can......I wouldn't drill a bigger size than specified though, but I would take time to see that the hole is cleared of all dust so the fixing goes in as it should.
John

 

[s60tsy]

also make sure you are not drilling towards the back edge of the brick

 

[Whitespirit66]

I think we'll have another go with the concrete screws. Unless someone has other suggestions? Is it recommended to use hammer-through fixings with UPVC?

Or would these Fischer universal FUR fixings be better?

http://www.screwfix.com/search?search=Fischer+Universal+Frame+Fixings

 

[Burnerman]

Personally I dont get on too well with the hammer through fixings of this diameter...I tend to chew the head up before they are fully tight.
Check out Screwfix 14004 fixings.....these push into the hole then rely on screwdriver tightening to do them up. Never fails!
John

 

[crank39]

The Fischer's are the original if you like window fixings but I think most people now use concrete screw's, both require the correct bit size, speaking from experience make sure your SDS bit isn't unduly worn if using Fischer as they'll snag when pushing them in, also do not over tighten them, they work like a rawbolt but do not grip like one and will strip easily, just nip them up

 

[Whitespirit66]

All sorted now. Got some Fischer SXR frame fixings. Really easy to use and did the job perfectly. The plug part was easy to tap through the holes in frame and brick, and with a little effort, the screws pulled up and gripped nicely when tightened. As you'd expect from a quality make.

The concrete screws we used previously were hit and miss - sometimes tightening, sometimes just spinning. The plastic tube type with the small plastic bit in the tip that travels up tube as screw turns were hopeless. Suppose I'm right in thinking that UPVC windows don't need to be too tightly screwed, as the ex. foam will add stability? I like a screw to grip a bit though.

Can't believe how something as simple as fixings can stump us but with practice the windows are going in nicely now.

Thanks to all for your advice.


http://www.screwfix.com/p/fischer-sxr-frame-fixings-10-x-100mm-pack-of-10/70578