We had a new garage fitted at the end of November- concrete wall pannels, mastik between the joints and metal roof and door. Its fitted where the older, smaller garage was and as such the base was extended.

A month on, and a very wet December- but i’m concerned as there is a lot of dampness in the garage- clothing etc is noticably damp and theres a lot of condensation.

Is this just part of the curing process (with the cooler tempratures and wet weather not helping matters) or is there something wrong?

Does the concrete need to be sealed (too early at this stage)/is it worth getting a de-humidifier/heater in there?

is there any insulation on the roof ?

if not the air is probably condensing on your roof and dripping to the floor.

just kingspan and expanding foamed my roof along with good ventalation in the walls – completely stopped it .

Sorry, my bad. NOT metal roof- metal facia, concrete wavy sheeting on the roof with “foam” inserts between the timber at the top of the walls and the roof sheeting.

Damp seems to be worst near the door on the floor at least but door appears to be sitting neatly in the housing.. Shelving at the rear is definetly damp too.

Could still be the concrete curing?

DP layer under floor do you know ?

is the ground outside set back to the door ?

mines used to in heavy rain run back into the garage so i installed a drain chanel across the front to chanel it into the ditch. problem stopped

Theres about 4/5 inches between the drive and the top of the base at the front. Less at the side of the garage.

Not aware of DP layer, wasn’t here when the base was getting done- my understanding was it was just extended to one side and lengthways but I don’t know without asking further as to wether the whole base has a fresh layer on the top too.

Its a new house to us, the old asbestos garage had been there for a while and was dry as far as I could tell.

Your concrete base could take up to a year to dry, depending on conditions, see http://www.concrete.org.uk/fingertips_document.asp?id=694

is the roof rusty?
because you know what they say- ‘rusty roof, smelly garage’

in all seriousness though, all that water that went into building it has to come out. the cold temps and high humidity at the moment mean that the air cant carry much moisture away so unless you can see some way that water is getting in, i would bung a dehumidifier in there for a few weeks

Mine is sodden at the moment. Neighbour had his half done with an EPDM membrane but built it up so it just ponds on mine. Mine used to leak occasionally but with it ponding the freeze-thaw action has totally wrecked it & meant its constantly dripping through. I’m planning to do it in the spring anyway, but till then I’ve had to put a tarp INSIDE the roof, & a length of guttering for it to run in to. 🙂

Get some of those plastic troughs with the absorbant granules in there. I put some in our caravan over winter.