Filling gaps so they won't crack

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cunningdavid

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#293731 10-Feb-2022 16:17

We have an upstairs bedroom that is supported by timber horizontal beams on pillars underneath. It has some gaps that doens't make it look the greatest, but it's been up for decades and as far as we know is structurally sound.

I've attached a photograph of the gaps between the timber components of the support. Does anyone know how we could fill the gaps to make it look a bit more, well, solid? The tricky part is that this support structure will inevitably move over time, and anything that doesn't have "give" to it will crack. Obviously a lick of paint will help too. Thanks in advance!

timbosan

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#2864838 10-Feb-2022 16:21

I would say just use No More Gaps - it can flex over time, however I assume at some point, if things are moving, you will need to redo it (or fix the underlying issues).

I just did some work (externally) on gaps around the (old, weatherboard) house, making it more waterproof for winter, and I use No More Gaps - easy to apply, dries well, can be sanded and painted.

Selleys No More Gaps Interior Multipurpose | Selleys

pih

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#2864841 10-Feb-2022 16:43

Houses move. I wouldn't trust anything to fill a gap that big and not crack over time, but if you're determined to fill it then No More Gaps would do it but if seasonal movement is large then silicone might be your best bet. Silicone is not paintable so it needs to be done after any painting you might want to do.

I'd actually just leave it as is, or if you want you spend some real effort, go down the path of attempting to cover the whole area, allowing for movement. This might mean placing an L-shaped metal/plastic plate over the joint, cut to the contour of the corner and fixed to one of the lesser moving pieces in the joint. Let it slide over the other pieces as your house expands and contracts.

If you're really keen to hide the joint you could box the whole beam, leaving enough room for movement around the pillar and other adjoining timber - that will leave gaps, naturally, but at least you can control where the gaps are and how they look.

timmmay

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#2864909 10-Feb-2022 17:12

No more gaps exterior is flexible and paintable. Might be worth a go. It will crack eventually. Otherwise I wonder if tape / plaster might work, but that probably needs a plasterer.

edge

edge
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#2864956 10-Feb-2022 18:22

Sikaflex MS is a fantastic product (modified silicone). It gets used heaps in our new house build!! Sticks like the proverbial to a blanket. It is very flexible and can be painted (once cured) with water-based paints. Worth considering maybe. About 4-5 times the price of No More Gaps but, in this case, I think you will get what you pay for in terms of performance over time. Only one possible issue I can think of is that it is best not to contact the "back" of the joint/gap for best performance - i.e. only touching both sides. It may not matter - but you could consider stuffing a narrow strip of polyethylene tape into the back of the joint before gunking to act as a bond-breaker - i.e. to prevent it sticking to the base of the gap.

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timmmay

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#2864994 10-Feb-2022 19:51

When using flexible fillers I suggest leaving more time to dry than they say, particularly if you're using oil based paints. If you don't the paint can crack.

OllieF

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#2865439 11-Feb-2022 13:48

You could try some rapid filla as well in the big spaces.

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MikeAqua

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#2865443 11-Feb-2022 13:57

Another vote for modified silicone adhesive-sealant. Because it's not just a gap filler, and sticks to the surfaces, it moves with them.

If something like Sikaflex doesn't work, try a 3M product called 5200. It sticks like xxxx to a blanket. After using it you will wish you were never born, but it is the best adhesive sealant I have ever encountered.

Mike

cunningdavid

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#2865495 11-Feb-2022 14:40

Thanks very much for all the replies!

Re the tape/plaster idea we did discuss this as an option with our plasterer (as well as no more gaps) but he looked rather unsure about the idea.

I will discuss the modified silicone idea with him though, as at a glance it looks ideal.

JayADee

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#2865563 11-Feb-2022 16:42

edge:

Sikaflex MS is a fantastic product (modified silicone). It gets used heaps in our new house build!! Sticks like the proverbial to a blanket. It is very flexible and can be painted (once cured) with water-based paints. Worth considering maybe. About 4-5 times the price of No More Gaps but, in this case, I think you will get what you pay for in terms of performance over time. Only one possible issue I can think of is that it is best not to contact the "back" of the joint/gap for best performance - i.e. only touching both sides. It may not matter - but you could consider stuffing a narrow strip of polyethylene tape into the back of the joint before gunking to act as a bond-breaker - i.e. to prevent it sticking to the base of the gap.

Brilliant, I have a use for this too. I'm going to try it.