Is time on my side?

[Aurelius]

Hi all

After removing all the internal plaster (read concrete!) from the inside of the external facing walls, I recently completed the base/levelling coat
I'm using the Ty Mawr system so next will be fitting of the 60mm Multitherm wood fibre boards using Isovit adhesive and Ejot mechanical fixings BUT I fear the clock is ticking
I was hoping to have this project completed before Christmas so a full heat pump/central heating system could be installed but my daughter had health issues over the summer, consequently the projects progress has been delayed. So now the clock is ticking and I'm concerned the seasons may be against me.

* According to the Ty Mawr website any newly applied substrate needs 28 days cure time prior to applying the Isovit adhesive and boards
* The hemp lime plaster top coat cannot be applied in sub 5 degree temps
* The ready mixed hemp lime bags have been in the garage on a pallet and covered in several dust sheets for nye on 3 months when the instructions advise to use with 4 weeks

At present my cottage has just a single log burner and a tiny oil filled rad in each bedroom and its very cold, So my questions are:

* Does the base coat really need 28 days to cure?
* Do you think the ready mixed hemp lime will still be ok to use?

Aside from having to throw the ready mixed hemp lime away, the worst case scenario is fixing the wood fibre boards in place and postponing the top coat and subsequent central heating until Spring when it warms up. (Far easier to apply the top coat prior to radiators and pipework being fitted.

Hopefully I'm being over cautious and I can just crack on with it but I'm grateful for any advice.

Regards

 

[Mulder]

You are worrying too much about it. I am not familiar with the guidance on allowing 28 days to cure before applying the boards. Makes sense I guess, but you can probably bring that in quite a bit depending how think it went on. Thicker = more time needed

I have used TyMawr Hemp lime that was in the bags for over 2 years! Went on fine and hasn't fallen off yet. I've still got a load sat in a barrel that I covered with a layer of water and plastic to keep the air out. Apart it now being super sloppy, it is still fine for my scratch coats onto brick. If it's gone hard, throw those bits away, but if it's still wet, you'll be ok.

You'll be ok with the temperature unless we have a sharp really cold spell or you're in a cold valley or something. Unlikely in the next month or so.

Worst case, you may need to reapply the top coat. But you'd be doing that anyway if you throw the lime away now. Make use of what you have

 

[Aurelius]

Thank you for the advice. If I do manage to complete the hemp lime plaster top coat, would having the new central heating switched on cause issues with it drying out too quickly?

 

[Mulder]

Yes, you don't want it to dry out too fast and crack. Equally you don't want it too freezing cold. Just keep the temperature low, keep the walls slightly damp for a day or so afterwards and keep an eye out for cracking.

Our cracked, even with no heating on. We kind of fixed them with a lime wash afterwards.

 

[Aurelius]

Thank you Mulder.
Apologies for firing queries individually but that's how my grey matter seems to work!
Can you give an estimate on how long the lime hemp will take to cure?
I've spent the last 7 years freezing through winter, so was hoping not to endure it again this year!