how to achieve smooth plaster finish over timber board + how to bond board to brick wall

[TofuSpaceship]

Hi all,

been humming and harring for months and months on how to finish this simple job at home, but I feel really uncertain on how to go about it, hence am here seeking some advice.

In our kitchen doorway we used a timber board as the door jamb; we used timber as opposed to plasterboard as the door on the other side is a heavy metal frame and needed a solid support to be fixed.
The timber board is fixed with screws into the bricks and kept in check with packers; there is a minimal give if pressed or pulled.

The intended final finish is plaster all around.

The doubts that left me stumped:
- how can I achieve a smooth plaster finish on a timber board?
- how can I infill the gap between timber board and wall to minimise the risk of plaster cracking?

 

[noseall]

If that timber liner is to stay, then it needs to protrude past the plaster line by about say 5mm. You then skim up to the back edge of the liner and fix architrave.

If it does not protrude past, fix a knock-on timber strip to it.

Get some foam behind the liner once you have fixed your knock-on.

 

[TofuSpaceship]

Thanks @noseall , should have made it is explicit though, requirement is to have plaster up to the corner and round covering the jamb and no architrave to be installed.

 

[big-all]

as wood expand and contracts you get cracks between plaster and wood so you need to cover this area or forever have the risk off cracks it may happen it may not but on that width off timber will almost certainly happen
in your instance the wood will go from perhaps 1 or 2mm proud to 1 or 2mm short off the surface

 

[TofuSpaceship]

Understood @big-all , how do you suggest covering it, with plasterboard? Attached to the timber how, with some (wood?) glue?

EDIT: sorry, tired brain. If plasterboard is a good choice for covering the timber, I can obviously use plasterboard screws to fix it!

 

[big-all]

the trouble you now have is whatever you do theres a big bit off wood that may or may not move even iff covered i simply dont know you may be lucky and it never moves from season to season it may move every few years it may move twice a year
i dont want to suggest drastic action as the result may not be worth the effort i simply dont know ??

 

[oldbutnotdead]

You might get away with wide mesh corner beads to bridge that gap (once you've filled it with exp foam of course) and bits of pb on the face of the lining. Long term you'll regret it, the corners will scuff up very quickly from people and things going through the passageway

 

[TofuSpaceship]

the trouble you now have is whatever you do theres a big bit off wood that may or may not move even iff covered i simply dont know you may be lucky and it never moves from season to season it may move every few years it may move twice a year
i dont want to suggest drastic action as the result may not be worth the effort i simply dont know ??

yeah totally understand @big-all, that is why I left this job hanging for ages! Thanks for your suggestions!

 

[TofuSpaceship]

You might get away with wide mesh corner beads to bridge that gap (once you've filled it with exp foam of course) and bits of pb on the face of the lining. Long term you'll regret it, the corners will scuff up very quickly from people and things going through the passageway

That is a very interesting suggestion, I just googled and there is out there some corner bead with very wide mesh, you can literally find anything online nowadays!
Do you mean we will regret it as in not fitting an architrave around the opening? or particularly about the solution of using that wide mesh corner bead and lining the timber?

EDIT: how would you attach the meshy bit to the already finished wall?

 

[oldbutnotdead]

That is a very interesting suggestion, I just googled and there is out there some corner bead with very wide mesh, you can literally find anything online nowadays!
Do you mean we will regret it as in not fitting an architrave around the opening? or particularly about the solution of using that wide mesh corner bead and lining the timber?

EDIT: how would you attach the meshy bit to the already finished wall?

I can see the appeal of the continuous plaster finish through the doorway, but the vertical edges will always take a battering from people and things passing through- give it a year or so and the plaster will scuff off the corner bead. Timber is more resilient and (not being brittle) doesn't show dinks in the same way.
Chop the finished plaster back a bit so the mesh sits flat, a few clout nails into mortar courses if you think it needs it but you'll get a good fix into the timber on both sides