Non Boaty: Anyone replaced an outside door frame?

[Ruffles]

Sorry to post this on a boaty forum but you guys may well have done something similar. (It's wood after all /forums/images/graemlins/wink.gif) Any advice gratefully received.

I can't leave it any longer. Our front door frame has to be replaced this Summer (when Summer gets here). It's an olde worlde cottage (i.e. damp) with a door to match. The concrete threshold is only an inch above the path and the frame is set into it so wicks up the rainwater well. Even the patches on the patches have rotted.

Rot at base:

The new frame will stop short of the threshold with the gap filled with mastic. Trouble is the frame will then have to be supported by the wall rather than held at top and bottom. Is there an accepted method of doing this? I know window frames are held in with foam these days - I assume this isn't strong enough for a door?

Having made an exploratory hole it looks like gap between the frame and the wall has been filled with rubble so I'll have to put 2" of render on the edge of the wall. So I'll have a good surface for masonry bolts. Is there a particular type of bolt that's used?

Gap between old frame and wall:

Frame set in threshold:

I hope I won't have to disturb the top?

 

[bigwow]

"I know window frames are held in with foam these days - I assume this isn't strong enough for a door?"

Foam, and a couple of long screws, have held both my front and back doors on up untill now, at least 8yrs. I think the walls would fall down before the foam gave way!

 

[Ruffles]

Thanks bigwow. Sounds like the way to go then. Is there a minimum and maximum gap it will fill?

I'm hoping to maintain the current fit between door and frame which is so good you can't get a piece of paper in there. Does the foam shrink at all as it sets?

 

[Captain Coochie]

The top should be morticed into the head (top) so it will come out with the rest of the frame . Thats a big gap , foam will do it but i would be tempted to nail a bit of scrap ply to the frame and fill with cement to get a good fixing for the frame .

 

[bigwow]

No the foam doesn't shrink. One tip I learnt was it sticks to everything, so mask off where you don't want it to go, it makes cleaning up a lot easier!

 

[mainmarine]

you can get long screws called frame fixings from B&Q etc, made for the job, after the frame is in place, you drill through the frame and into the masonry, then insert the frame fixing, it has a large plastic rawlplug on the end, then screw in the screw, job done.
As said before make sure the masonry is sound behind where you intend to fix.

 

[Ruffles]

[ QUOTE ]
The top should be morticed into the head (top) so it will come out with the rest of the frame . Thats a big gap , foam will do it but i would be tempted to nail a bit of scrap ply to the frame and fill with cement to get a good fixing for the frame .

[/ QUOTE ]

I thought it would be but I reckon I can saw off the old frame and take out the remains of the tenon with a mortis chisel. I plan to put the new frame in with a 3/16" gap at the bottom so I stand a sporting chance of getting the new tenon in. Of course the top may just fall out anyway.

Suspect the gap will be even bigger when I've finished. I've some block board to build a cast for the concrete.

Thanks,

 

[Ruffles]

I'll have a look.

Thanks,

 

[andrewbodenham]

The place to ask about this sort of thing is the excellent forum on Periodproperty.co.uk, where you'll find a nest of old house enthusiasts bristling with good advice.

I've done this job on several houses and know a few of the pitfalls.
Stopping the frame short of the ground / sill is good to prevent the end grain wicking up water. To provide support I usually sit the frame on a couple of plastic packers, then fill around with mastic. Worth sealing the end grain with paint etc. before installation.
Fitting the frame may be easier if you simplfy the joint between the head and stiles. Once installed all the head has to do is resist the inward thrust from the weight of the door, so a simple rebated joint can be used instead of a through tenon. This allows the frame to be assembled in-situ. Glue up with PU and wedge tight whilst it goes off.
For fixing I'm a fan of Mulit-monti screws (see Screwfix) which are bombproof in most substrates. Expanding foam provides a good fix, but I'd not rely on it alone for an external door frame. Before foaming blow / hoover the surfaces clean and lighty mist with water to promote curing.
When making good the mortar work up to the new frame it's a good idea to leave a movement gap between the mortar fillet and the frame. You can create this by pinning strips of thin corrugated card to the face of the frame before mortaring up. A layer of parcel tape will stop the card going soggy, and allow easy removal once the mortar has gone off. When cured fill the gap (2 -3mm) with non-setting mastic. I use polysulphide, as it is durable and paintable.
As with boat woodwork, the care taken in detailing will determine the effective life of the work. Consider the reasons why the original frame has failed and aim to design these out of the new installation.

 

[Ruffles]

Brilliant stuff bodfish.

The base of the door rotted for the same reason. When I scarfed pieces on I wrapped the base of the door in cling film and poured in some undercoat. By slowing the paint cure I hoped it would soak further up the grain. Seems to have worked.

Thanks for the pointer to the web site. Are there any books on this sort of stuff? Something old fashioned without the dire warnings and building regs stuff that frankly doesn't suit maintaining old houses. Our lounge floor is 2' below outside ground level. Some walls are solid brick, others are sandstone! So something that covers damp would be good!

 

[alant]

Supplier of non-standard doors/frames??

Not quite as old as yours, but I have a similar problem with an outside, outward opening side door on my garage.

Need to change door + frame, but not a standard size stocked in B&Q etc.

Anyone know of a supplier in Bournemouth-Southampton are, for non standard frames/doors?