MDF mould rescue or ditch?

Dustyevsky

I would clean them up and then give a coat of Creocote, but I'm a 'farmer!'

If likely to warp, I'd glue and screw a batten to the underside.

All my stuff in the chicken shed is 15 years old and treated that way, but it's mostly ply and softwood. No mould, rot, woodworm etc.

moneysaver1978

We have the bitumen, masonry, shed, fence paint but no PVA or anything like that.

The shelves seem to be ok. Latest after I gave them a good clean yesterday with vinegar spray  - apologies for the mess (the rain was on its way so had to quickly stuff everything back in the shed!):

ThisIsWeird

They do come up well, so that's good news - it suggests the affect-effect is purely cosmetic.

Masonry paint is great stuff - practically a 'universal' paint. Well-thin the first coat, and roller on. Allow to fully dry. Then one or two top coats.

But make sure the boards are fully dry first.

moneysaver1978

ThisIsWeird said:

They do come up well, so that's good news - it suggests the affect-effect is purely cosmetic.

Masonry paint is great stuff - practically a 'universal' paint. Well-thin the first coat, and roller on. Allow to fully dry. Then one or two top coats.

But make sure the boards are fully dry first.

Perfect thank you! Busy next few days with Christmas, so will get back to the shed in the new year - hopefully by then they’ll be fully dry and the mould don’t come back!

poppellerant

You can buy anti-mould additive that you can add to paint and that's what I'd use in this instance.  Below is a link to an example of such additive:

https://www.amazon.co.uk/dp/B07NJBC9QP

casper_gutman

I think I'd probably have cleaned these up and kept them, so well done for giving it a go. I hope you took appropriate steps to avoid breathing in all the mould - mask, ventilation, dampening everything to wipe it down, etc.

If the clean-up job doesn't work out and the mould comes back in short order, I'd look to replace the boards themselves and keep the metal frame. It seems a shame to scrap all that material (and embodied energy/carbon). A sheet of material more suitable for damp conditions - OSB or thin exterior plywood - would be easy to cut to the right size. If you go to the right timber merchant or DIY shed they'll probably cut it to size for you.

moneysaver1978

Happy New Year!

Follow up photo as promised - only a few patches have the mould back.

So I have sprayed again with vinegar. 

The metal shelf frames are great and I agree that it would be a shame to ditch (although I would freecycle) but maybe not MSE if the wood is more expensive than the whole unit.

teaselMay

A sheet of OSB would likely cost more than the whole unit, but if it means it's usable and non mouldy may still be the most economical way to sort it out. If you were to buy from B&Q you could ask them to cut a big sheet to the right size too

ThisIsWeird

moneysaver1978 said:

Happy New Year!

Follow up photo as promised - only a few patches have the mould back.

So I have sprayed again with vinegar. 

The metal shelf frames are great and I agree that it would be a shame to ditch (although I would freecycle) but maybe not MSE if the wood is more expensive than the whole unit.

The actual board appears to be perfectly fine - fully solid, with no signs of swelling or anything. Absolutely no need to consider replacing these. What thickness are they?

Have you tried 'mould killer' by 'Astonish? I'd be inclined to try a light spray of this, and just leave it to dry.

moneysaver1978

ThisIsWeird said:

moneysaver1978 said:

Happy New Year!

Follow up photo as promised - only a few patches have the mould back.

So I have sprayed again with vinegar. 

The metal shelf frames are great and I agree that it would be a shame to ditch (although I would freecycle) but maybe not MSE if the wood is more expensive than the whole unit.

The actual board appears to be perfectly fine - fully solid, with no signs of swelling or anything. Absolutely no need to consider replacing these. What thickness are they?

Have you tried 'mould killer' by 'Astonish? I'd be inclined to try a light spray of this, and just leave it to dry.

Thanks @ThisIsWeird! The thickness is around 6mm so not that thick.

Hadn't considered purchasing a mould killer spray as I was using whatever we have before leaving over Christmas holidays!

It's raining too heavy today for me to take them out and paint (not keen on bringing these boards inside the house!).