How to fill in gap in architraves beside bathroom tiles?

Question

Hi All,

I'm looking for some advice on how to fill in this gap in the architraves without replacing them as I don't want to disturb the tiles.

Its about 30mm deep from the front face of the architrave to the wall behind. 200mm long and widest opening is 5mm.

Looking for something which I can shape/paint and is solid enough to hold up without crackling.

Cheers,

LV

JacobZ · Answer

Hi @LowVolt,

I completely understand the concern, but given it is in a bathroom, bog is the only filler I'd recommend because products like plaster fillers which are easier to work with are much more susceptible to issues with moisture.

If you tape off both sides of the gap, and slowly pack your bog in, building up layers as you go, I don't think you should really have any issues. Press small amounts into the gap and work along it tidying up as you go. For really precise stuff, I always use one of these

https://www.bunnings.com.au/uni-pro-25mm-real-good-paint-scraper-25mm_p1674074

. I'd highly recommend it in this scenario as it will only allow you to move a small amount of bog at a time, so it in a way forces you to be precise.

Builder's bog is also two parts, the filler, and a hardener additive. If you use less hardener than usual, it will give you more working time to get it pretty close to perfect.

If depth is a concern, you can also push some foam filler rod into the gap before building the bog up over the top.

Let me know what you think.

Jacob

LowVolt · Answer

Hi @JacobZ

Thanks for the reply. I had thought about using bog but I wasn't sure if it was going to be possible to pack it in enough to build a solid surface to work with given how deep the gap is compared to how narrow the opening is - especially near the top where it gets narrower.

At a 5mm I'm worried its going to be a push to get bog into the gap. Any advice on how to handle that?

Given how nasty bog is to clean up I don't want to get this wrong and end up making more work for myself. 😅

JacobZ · Answer

Welcome to the Bunnings Workshop community @LowVolt. It is wonderful to have you with us.

Start by cleaning up the damaged section of the architrave. Remove any loose timber and splinters, then sand the edges smooth so you have a solid, tidy surface to work with.

I’d then tape off the tiles to protect them and build the damaged section back out using Turbo Builder’s Bog. Apply it in stages with a metal scraper, shaping it as closely as possible to the existing profile of the architrave. Builder’s Bog sets quite hard, so getting the shape reasonably close before it cures will save you some sanding.

Once it has cured, sand it back until it blends neatly with the existing timber, then prime and paint the repaired section.

Finally, I’d run a small bead of Selleys Wet Area Silicone along the seam where the tile meets the architrave. This will give you a neat finish while allowing a little movement between the two surfaces.

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob