Conservatory ....fixing cill to dwarf wall ?

[bisto36]

Can anyone clarify the procedure ?
The instructions I have with my conservatory ( and other manufacturers instructions I have seen) , imply that when the cill is fitted on top of the dwarf wall , it is actually "floating" and that although you fix the frames to the cill , the cill is not actually secured to the dwarf wall ?

Is this correct ?

doesn't sound too secure to me ?? !!

Any advice would be helpful

 

[Symptoms]

bisto - timber or plastic? Timber structure should have a mechanical fixing (frame fixings, plug & screws, strapping or similar depending on construction). I know nothing about uPVC constructions but others here will; maybe, the instructions for a plastic jobby allude to expansion issues. Still, won't there be a danger of you becoming the proud owner of a big kite during the next big wind if it's not fixed down in some way?

 

[bisto36]

The conservatory is "plastic" , Kommerling is the brand , if it makes any difference ?

I was also thinking about the "big kite" issue , lots of wind up here in the Fens !!

 

[noseall]

connie installers pack the sill on plastic packers leaving a deliberate 10-15mm gap beneath the sill.

this is later piped full with silicone from both sides once the external installation is complete.

or you can silicone seal the outside and pipe expanding foam into the void from the inside prior to fitting the window boards.

in the old days we would have bedded on compo (mortar).

 

[bisto36]

Thanks noseall for the info ! That has put my mind at rest

So basically the intructions are correct , and it is kind of "floating" on the wall.

Just out of interest , anyone know why it is not secured to the dwarf wall with screws etc ? Is it to allow for expansion/contracton etc ??

 

[noseall]

it is not wise to try and mechanically fix to the final course of brickwork in any situation.

gravity will keep it down and the cohesion betwixt sill and masonry will prevent slippage.

 

[Symptoms]

After the pub last night friend of mine showed me the installation instructions for his plaka conservatory ... quote:

"Fix the frames to the base/dwarf wall with
8mm x 120mm fixing bolts (1 per panel 2 per french
door) Fix to the parent wall with a further 2 bolts (dwarf
wall) or 3 bolts (glass to ground)".

So his was mechanically fixed to the dwalf wall & house wall (just like my wooden one as per earlier post). So maybe there's no hard & fast rule about fixing ... just follow the manufacture's instructions.

Noseall - agreed about the final brick course hence my ref to strapping.

 

[IJWS15]

Mine (Wickes) says you screw the cill to the wall every two feet (sorry 600mm). Came with fischer window fixings for the job. Would have taken a hell of a lot of silicone to fix ours down (8m wide P shape). Did not come with packings but bought some window packers and used these each side of every screw position to set the cill level and checked level before and after the screws were tightened. About half the build time was spent getting the cill right.

Granted it is not much brick for it to lift but it also fixes to the wall at the ends and along the roof. You also have to remember how much the conservatory itself weighs.

Been up two years and never moved - and we have had some strong winds in that period.


Interesting bit was that general accuracy for spirit levels is 0.5mm per m and that equates to 4mm over the width of our conservatory - not accurate enough.

 

[bisto36]

Thanks for all your replies , I think I will follow the instructions I have which say that the "cill floats" , and that the frames screw to the cill.

But it was interesting to see some of you have differnt conservatories with different methods of fixing ?

 

[DaG56]

connie installers pack the sill on plastic packers leaving a deliberate 10-15mm gap beneath the sill.

this is later piped full with silicone from both sides once the external installation is complete.

or you can silicone seal the outside and pipe expanding foam into the void from the inside prior to fitting the window boards.

in the old days we would have bedded on compo (mortar).

Why is that no longer done?

 

[IJWS15]

connie installers pack the sill on plastic packers leaving a deliberate 10-15mm gap beneath the sill.

this is later piped full with silicone from both sides once the external installation is complete.

or you can silicone seal the outside and pipe expanding foam into the void from the inside prior to fitting the window boards.

in the old days we would have bedded on compo (mortar).

Why is that no longer done?

Would like to see someone try . . .

The Wickes instructions say bed on mortar then fix down. Could not see how this would let me get it level (8m wide P shape) so set on packers, fixed it, then packed with mortar.