Concrete screw length for installing Upvc windows.

[Discoeye]

Hi to all. Bit of a mixed bag of questions so can anybody recommend a Concrete screw length for installing Upvc windows , the house is solid 9 inch brickwork so no cavity and the bricks I would describe as a soft red.

And to coincide with this what drill bit length, I thought a 260mm /200mm working length 6mm sds+ so as to get enough into the brickwork but be clear of not being to close to the window jamb when drilling.

[bassanclan]

100mm long screws (some companies make them 102mm) have a few drill bits different lengths. 6mm and 6.5mm to overcome problems, blunting or breakages

[Discoeye]

Thanks for the reply, I have seen some go up to 150mm + I presume those would be for larger windows/ doors . So 100mm is fine my windows are all pretty much 900mm wide/ 900mm tall.

[jayc89]

I was planning on using 100mm screws for our windows. The only time I've used longer is for our internal wall insulation where they needed to go through battens, insulation and then into the wall. 

[markc]

When it comes to fitting windows and door frames, length of fixing is just enough to get into solid material as the fixings are in shear (albeit with some bending but that really complicates any calc)…. (Im not mentioning big gaps between frame and surrounding or that complicates things even more). Only when fixings are in tension is minimum depth critical for pull-out resistance.

[gaz_moose]

100mm. i used the screwfix ones, they come with a star drive impact driver bit too match the screws. then 6mm sds drill bit with a 100mm drill length.

[Discoeye]

Thanks everybody a great insight into peoples thoughts on the subject, thanks gaz_moose I have seen those ones in screwfix as well as some ridiculous priced ones.

[markc]

Oh bugger, no idea why auto correct put covid instead of solid 🤯

(We have edited it now - but still amusing and we can put it back if you wish. Admin)

[Carrerahill]

4 hours ago, Discoeye said:

Hi to all. Bit of a mixed bag of questions so can anybody recommend a Concrete screw length for installing Upvc windows , the house is solid 9 inch brickwork so no cavity and the bricks I would describe as a soft red.

And to coincide with this what drill bit length, I thought a 260mm /200mm working length 6mm sds+ so as to get enough into the brickwork but be clear of not being to close to the window jamb when drilling.

260mm sounds pretty serious, are you expecting a hurricane? Remember the fixings are just the start of the fixing "system" the fixings are in shear so don't need to be particularly long to achieve a good fixing to the building. I would probably use 75mm Fischer fixings but to be honest, if the framing, silicone, external treatment (i.e. fully rendered in solution or full silicone) then all of this adds to the fastening solution. 

[Discoeye]

Did wonder about the covid material🤣markc. And Carrerahill after catching my breath from laughing at the hurricane I did picture myself drilling through to my neighbours and supporting their window to.

Thanks everybody.

[Dave Jones]

dont butcher the frames use straps, can plug and screw then.

[Discoeye]

Quick thought do I need a clearance hole through the frame for the screws or can I go straight through with the pilot then the screw.

 

Thanks all

[bassanclan]

Just go straight through with 6mm sds, or better still use straps

[Discoeye]

Thanks👍

[MikeSharp01]

Shouldn't you be using frame anchors rather than going directly into the Brick work, you need to avoid splitting the bricks I would have thought!

[jayc89]

1 hour ago, MikeSharp01 said:

Shouldn't you be using frame anchors rather than going directly into the Brick work, you need to avoid splitting the bricks I would have thought!

 

PVC windows have been fitted like that for the last ~ 50 years? There are certainly pros to using straps, but they're likely minimised on a solid brick wall, without some additional detailing. 

[Discoeye]

Good morning all, following on from my previous question can anybody recommend a suitable screw and length for attaching the cill to the window frame.

Thanks.

[Dave Jones]

23 hours ago, jayc89 said:

 

PVC windows have been fitted like that for the last ~ 50 years? There are certainly pros to using straps, but they're likely minimised on a solid brick wall, without some additional detailing. 

 

yes, shoddy practice fixing them outside the thermal insulation. Now they have to do it properly there isn't any brick left to drill into by butchering the frame. Max 30mm.