# Bifold Door Installation - Fully finished Vs In-Situ Build



## Jelly (17 Feb 2021)

My workshop renovation is moving along to the point where I'm ready to install the new main door(s?) Which will be three 1962×642mm half-glazed framed, ledged and braced doors, running in a tommafold 60 bifold track.

Whilst I've built a great many doors (and windows) in my time, that was in a production environment, and I never got involved with fitting them, so don't have the practical experience to decide how best to proceed...


I was originally planning to cut all the frame components, and prepare the doors, then in a single day:

Remove the existing garage door,
Bed the Cill level on quick setting mortar with concrete bolts holding it down
Assemble the legs and head onto the Cill.
Attach the legs and head to the walls & lintel.
Mount the tracks
Install the doors
Make final adjustments to the lock hardware positions and install.
All of which depended on the assistance of a couple of friends, who of course can't actually come help in the current climate.


So I got to thinking about assembling it as a fully finished unit, much as I would have with standard sized doors when I did it for a living (although without the benefit of alignment jigs and pneumatic clamping tables)...

Installation then becomes a case of simply:

Removing the garage door
Erecting the frame, replete with doors into the hole, and screwing some battens to the lintel to prevent it falling.
Leveling it up on toe-jacks/wedges
Adding packing at the sides and screwing the legs to the walls
Trowelling the bedding mortar under the Cill,
Screwing the head to the lintel.
Which could with care and some mechanical aid, be done on my own.


However, I have pause for thought over the potential to assemble a perfectly square frame on the floor of the workshop, only for it to end up racking or out-of square when manhandling into position for installation.

The frame sections are pretty substantial (100×125 Head, 75×100 Legs, 75×200 Cill), so with good joints should be quite stiff on their own.

But I'm figuring that with such a large opening (1962×1926) it would need several braces screwed to the frame (and each other) to ensure everything was held dead square, and I'm not entirely sure what the best bracing arrangement would be to achieve that.

I don't think any amount of bracing can guard against the risk of racking, and that will come down to careful inspection prior to and repeatedly throughout the process of securing it, possibly adjusting slightly with clamps or mallet blows before installing each screw.


Any advice or suggestions very much welcomed.


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## Doug71 (17 Feb 2021)

Whichever way you do it Air bag wedges are your friend, grab 4 packs from Lidl on Thursday. 

The second method is probably best because you can check everything fits square before you screw the frame back.

Concrete screws are great for fixing, the type that don't need plastic plugs. 

Just get your frame packed nice and square/straight using the air wedges then drill and screw straight through the frame into the wall with the concrete screws.


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## owen (17 Feb 2021)

Jelly said:


> My workshop renovation is moving along to the point where I'm ready to install the new main door(s?) Which will be three 1962×642mm half-glazed framed, ledged and braced doors, running in a tommafold 60 bifold track.
> 
> Whilst I've built a great many doors (and windows) in my time, that was in a production environment, and I never got involved with fitting them, so don't have the practical experience to decide how best to proceed...
> 
> ...



I would do it the second way you have suggested, but I wouldn't worry too much about bracing it, a couple across the corners will do, just make sure you check and double check everything with a spirit level as you install it and it'll be fine. I would get someone to give you a hand for half hour once you have assembled it on the floor just to lift it into place, it'll be almost impossible not to twist it doing it on your own


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## LBCarpentry (21 Feb 2021)

Frame in and squared up using pump bags.

Foam & leave to set

cup of tea and a biscuit time...

Only once set you then drill/pilot and fix with concrete fixings. Foam acts as the perfect packer

Remove pump bags and fill the void that they leave with foam.

Louis


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## mikej460 (21 Feb 2021)

I'd caution you to use proper framing foam as fully expanding foam can push your frame out of true.


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## Jelly (21 Feb 2021)

Thanks everyone!

I'm now fully convinced on building it as a fully finished unit, and fitting it last now. Much better shout.



LBCarpentry said:


> Frame in and squared up using pump bags.
> 
> Foam & leave to set
> 
> ...



Hadn't considered using foam, was planning to hew/plane packers from scrap wood, screw in place then fill the remaining gaps with mortar before fitting the architrave and external trim.

However combined with Mike's info below it sounds functionally very similar and much much faster.




mikej460 said:


> I'd caution you to use proper framing foam as fully expanding foam can push your frame out of true.


This is extremely useful advice, as it's exactly why I wasn't planning to use foam, thanks!


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## owen (22 Feb 2021)

Jelly said:


> Thanks everyone!
> 
> I'm now fully convinced on building it as a fully finished unit, and fitting it last now. Much better shout.
> 
> ...



I would get the frame in place, use folding wedges and screws to hold it, then lastly foam. Foam won't tend to push the frame out of place along as it has somewhere open to go (the gap that the architrave will cover). I don't know what framing foam is but I've used normal expanding or fire foam on hundreds of door frames and not had any move.


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## clogs (22 Feb 2021)

we just used 1/2 ply air nailed to the corners.....full sheets where poss.....
this kept everything square......fix the frame in place and a quick check...
with packing wedges etc secured in place....job done.....
framing foam was not invented when we did it...
often they were 4 door units.....
for framing, we always doubled what was needed for the lower frame part where poss....apart from proper corner joints, glue and screws, often had custom made st/steel corner plates (hidden from veiw) fitted just as insurance......
the frames for this kind of door job need to be tough......


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## RobinBHM (22 Feb 2021)

Jelly said:


> I'm now fully convinced on building it as a fully finished unit, and fitting it last now



Yes def best to get frame set up and doors working.

You don't need to square up the frame when setting up....just ensure your doors are dead square and adjust the frame to that.


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## LBCarpentry (22 Feb 2021)

Jelly said:


> Thanks everyone!
> 
> I'm now fully convinced on building it as a fully finished unit, and fitting it last now. Much better shout.
> 
> ...


Nothing more annoying than squaring up a frame with packers and then knocking it all out if square with the first squeeze of hammer drill!


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