Attaching fram to lintel

[parksy]

Hi

I am installing a 3metre wide folding sliding door (fsd) into a rendered cavity wall. The lintel is a catnic cavity lintel. The height of the frame is 40mm less than the opening. My intention is to attach a 40mm thick board to the underside of the lintel which I can then attach the doorframe to or alternatively pack out the top runner of the fsd and fix it straight to the lintel

My question is about how I should attach to the lintel? Can i bolt through the lintel into the concrete blocks behind or should I use adhesive? Can I drill the bottom plate of the lintel? Would adhesive be strong enough - especially as the top runner of the folding sliding doors carries the whole weight of the glazed doors.

Many thanks in advance for your help
Chris

 

[keyplayer]

I suggest you fix the frame sideways into the brick/blockwork, and take up the 40mm gap with expanding foam. (not too much as it can buckle frame). Have seen this done a lot.

 

[parksy]

I think I need more support to the lintel - the top track is 3 metres long and takes the weight of the doors so I really need to attach it to the lintel - otherwise it will sag in the middle. At the moment I think I am going to use something like 'timbadeck' screws to attach to the lintel. These will self-tap though the steel of the lintel and will countersink into the track.

Chris

 

[masona]

Can you not use wide L-shape bracket and self-tap it into the metal lintel and screw it to the frame then architrave to cover the bracket? I've got some from Wickes yesterday and they do many type of width and length brackets

 

[parksy]

Hi Masona

Thanks for your help. I might go that route.

If you were to do that what would you do on the outside? It is going to be rendered on the outside so I am assuming that I need at least a wooden trim over the gap between the top runner and the lintel, which comes flush with the outside of the wall, which can then be rendered over - or alternatively just a wooden trim to cover the gap between the render and lintel and which won't be rendered.....

Chris

 

[masona]

If it was me, I would use sharp sand & rapid cement to fill the gap then smooth it off on the front, let it dry then render to it.

Fix the brackets first before sand/cement.

 

[parksy]

Thanks for your help Masona. I will give that a try - sounds like a good solution. Thanks for your suggestions.

Chris

 

[masona]

Forgot to add, make sure the the top frame is straight and not bow when backfilling with sand/cement, might be an idea to temporary support it with timber studs until cement is hard and there's nothing stopping you to put in extra self-tapping screws through the frame and cement to the lintel if needed.

 

[parksy]

Thanks for all your advice. I put self tapping screws through the frame into the lintel and backfilled with cement. It's good and level and very solid.
Thanks again
Chris