Dehumidifier advice following building works, please

ih8stress

Hi, recently had a conservatory with a concrete floor replaced with an extension (3m x 5m).

This was open to the elements for around 3 weeks in November/December and I am trying to dry out the floor and newly plasterboarded walls.

I have currently got a Meaco dehumidifier in there, which is slowly helping, and now the plasterboards are almost dry, have introduced occasional heating too (no electric or radiators installed yet).

I am considering getting an industrial dehumidifier to speed up the process. A family member is currently having a summer room built, been raining constantly for over a week now, so the exposed floor is soaked!

We are wondering if it would be better to buy an industrial dehumidifier between us (or maybe a crawl space dehumidifier?) with the intention of selling it on afterwards OR to hire one as the costs will probably be similar?

Don't fancy second-hand from evilbay, or anything from Amazon.

Appreciate any advice and thoughts, please :) Especially if there are other options or we actually need a different product altogether.

WIAWSNB

The single best solution is to open all the doors and windows as far as you can without letting more rain in, and ventilate the place.

Jobbie jobbed.

Section62

https://forums.moneysavingexpert.com/discussion/6652415/dehumidifier-advice-following-building-works-please

Generally it is better to allow the building to dry out naturally. Using an industrial dehumidifier may get you a rapid result, but the rapid drying can have negative effects on the strength and durability of materials and/or result in excessive movement.

For example, it takes a long time for mortar/concrete to gain full strength through a process known as 'hydration'. The name comes from the process being a chemical reaction requiring enough (but not too much) water to complete. If there is insufficient water (for example if the space is dehumidified) then the process ceases before it is fully completed.

Likewise, materials can swell and shrink depending on moisture content. Drying them too rapidly can create stresses leading to splitting and cracking. More gradual drying allows the material time to adjust to changing moisture content.

ButterCheese

I'd go somewhere in between. A lot of the so-called domestic dehumidifers online are pretty pathetic; my partner bought one a few years ago which is something like 150watts. It fills up it's tiny 1 L tray in about 12 hours. It has flashy lights and is curiously very heavy, but it's not much more than a glorified fan.

In contrast, I have one off Amazon (which I bought about 10 years ago for £130) which is still domestic in size (and it's white) but it has a 2.5L tray which it fills up in about 5 hours. Like most sites these days, they seem to quote the actual measurements of the thing, and the colour, and how loud or quiet it is, without telling you much of the technical details. Maybe try to find an affordable one from a hardware store or machine shop, or trawl through Amazon to find a good one rather than a flashy fan

WIAWSNB

You either USE a dehumidifier, which means keeping that area sealed off as much as possible from external influences - closing all the doors and windows - or you do the sensible thing.

jennifernil

If you wish to use a dehumidifier, I would just continue using the one you have, then lend it to your family member.

WIAWSNB

https://forums.moneysavingexpert.com/discussion/comment/81856918#Comment_81856918

Ideally covered in vaseline...

jimi_man

When we had an extension we were told to let everything dry out naturally with windows open, but not with any artificial drying.

ih8stress

Thank you to everyone for the replies so far, much appreciated.

The difficulty is that there is still one full wall to be plasterboarded, probably within the next week and once that is dry (around 5 days minimum?) and the electrics and radiator done, I will have to re-lay the carpet and move all my furniture and stuff back into the room. Decorating will be done at a later date.

I am just worried about my stuff being ruined if it is still damp and creates future issues

WIAWSNB

As long as you keep the room well ventilated, it should be fine.

Keep furniture away from walls - allow air to circulate.

Lorian

I trust the building is weather tight? Hard slow work with a compressor dehumidifier this time of year. More heating might help otherwise a dessecant dehumidifier.

Notwithstanding what others have said about natural drying of course, but where I live we haven't had more than a few drying hours in weeks.