Rot Doctor

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Subject: How do I best repair this (stair beam)

Date: Thursday, April 23, 2020

Hi there. I have outdoor stairs with beam that has dry rot. I’ve read a bit on your site, but would love for you to confirm.

Stair beam, view from the top Stair beam, view from the bottom Stair beam, close up with hand for reference

1. I’ve chipped out as much rot as I can. It has been drying out for two days now and feels much drier.

You want it dry enough that it doesn’t feel damp to the touch, and water can’t be pressed out of the surface, or drill bit tailings can’t have water squeezed out. From the images, I would be most concerned about the wood the goes below the level of the concrete. That is more likely to be wet, and more difficult to dry out.

2. Now do I need to Coat with layer Of epoxy and let dry? Then make a soup with epoxy and wood chips? fill in in a couple steps?

After getting the wood dry, the next step is to allow S-1 Sealer to soak into the wood, as much as it wants to take. Once saturated, this will take 2–4 days to dry, depending on how much S-1 is soaked in. When it isn’t sticky to the touch, and doesn’t smell of solvents, it should be fine to start filling in. I would start with some Sculpwood Epoxy Paste, and fill in the cracks and holes on the end of the stringer. After this had 4–6 hours to harden, then pouring a more liquid resin in could be an easy way to fill the void, if a form was used to keep the liquid from running out. With a rougher surface to the wood, this can be more difficult. It may be easier to just keep using the Sculpwood Paste, with pieces of wood, if you want to use less Paste, and build up in layers.

The biggest area of concern is what is going on below the level of the concrete. If there is wood down there, it might rot in the future, giving the repair an unstable base to sit on.

What products? What amount? Are wood chips versus sawdust doable? Other thoughts?

S-1 Sealer, 2 quarts, to be safe. Sculpwood Epoxy Paste, as much as it takes to fill the void, if you are not going to use a thinner filler like the General Purpose Epoxy Resin. For over all ease of the repair, I would recommend filling just with the Sculpwood Paste. You might have to do 3–4 layers to get it built back flush, but you can do 2–3 layers a day, and wouldn’t have to worry about a form leaking.

Thank you in advance,

That is all the thoughts I have at the moment. If you want to discuss in detail, it might be best to do via a phone call.


[Miscellaneous Q&A Index]

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