Stair tread damage - repairable/replaceable? (photo)

Question

The staircase had carpet, we want to remove the carpet and paint the stairs in their "wooden" state.

On removing the carpet we have treads like this:

We do not have access from "behind" the staircase.

Is this repairable or replaceable in a reasonable time/budget? (not "you'd have to dismantle the whole upstairs" level of complexity).

Edited to add: is it normal for treads to crack this way or do I have a more fundamental problem? House was built in the 1960s, I don't know if the staircase dates back to then but probably it does.

Edit2: Happy to go with a cosmetic "less than ideal"(visible cracks etc) as long as it's structurally sound.

Answer 1

If it's easy to remove the tread (and it may be) it's likely easiest to just replace it.

If it's not so easy to replace it, what you could do is put in a couple of pocket screws using a pocket screw kit. Kreg is a popular brand that makes pocket screw kits that you can find at most any big-box store.

You'd set up the jig, drill your holes, squirt a bit of wood glue into the crack, then screw it together.

You then fill the screw holes by gluing the included wood plugs in, give it a sand, and ready to paint.

Answer 2

That's a very wide piece of wood, and, unsurprisingly, it cracked. However, assuming that it structurally sound, the easiest way to fix it that will look reasonably good is

1. Cut a long thin wedge-shaped piece of wood that matches what you have (I'd guess pine); the piece should look like a long knife)
2. Clean out the and scrape it down with a chisel
3. apply wood glue into the crack
4. Put your knife shaped piece of wood in the crack and hammer it until it is firm.
5. Wait until the wood glue dries, and cut/plane off the remainder of the wedge you inserted.

You can see an demonstration here: crack filling

Answer 3

I would do this for a quick, strong fix, assuming the wood is not loose or rotten:

1. Get yourself a tube or two of heavy duty construction adhesive (Liquid Nails, Titebond, etc.). Inject a bead as far into every joint as you can, both where the treads are cracked and where they meet the risers. Carefully scrape off any adhesive laying on or above the wood surface. This will effectively bond the boards together and prevent squeaks and creaks (as much as can be done without completely disassembling the staircase).
2. Allow that to cure for at least 3 days, until it has shrunk as far as it's likely to and firmed up well. If needed, apply duct or packaging tape over the joints to keep footwear from picking up adhesive.
3. Skim the joints with a good quality, sandable wood filler per the product directions. Once that's cured, sand with a random-orbit sander or sanding block. Prime and paint.

Be aware that nothing short of a retread with engineered wood will prevent any of those seams from appearing through the finish. That's probably not a reasonable expectation.

Also be aware that painted stairs are slippery. You may be careful to prevent falls, but visitors to your home won't know to use caution.