Damp garage floor

mutley74

Our garage (single type) built over 25 years ago by previous owners does experience damp patches across the concrete surface. This is especially noticeable during periods of heavy rainfall. Some of this damp has rises at the garage walls (single brick construction). No damp enters the house.
It is likely that the garage has no damp proof course on the concrete floor, as previous house owner seemed to have cut many corners to save costs.

A builder suggested we lay a DMP and 3" of concrete on top of the existing. Other option he suggested was to dig up existing concrete floor and replace.
Obviously we do not prefer latter due to the amount of work and mess involved.

Any other suggestions welcome please on possible options we can consider.

Imp

As it is a garage, could you not just leave it?

mutley74

Imp wrote: »

As it is a garage, could you not just leave it?

Yes we could but looking for a low cost straightforward solution if possible to at least reduce/limit the dampness. We use the garage as a general storage so it would be ideal if we could stop it.

Tucker

Are you sure the moisture is coming up through the floor?

Is it possible that it's seeping in through the brick walls? Is the height of the ground outside the garage higher or lower than the garage floor?

My dad's garage was the same, but making a small trench around it and filling with stone solved the problem, as the water was finding it's way in from three sides and not up through the concrete base.

mutley74

Tucker wrote: »

Are you sure the moisture is coming up through the floor?

Is it possible that it's seeping in through the brick walls? Is the height of the ground outside the garage higher or lower than the garage floor?

My dad's garage was the same, but making a small trench around it and filling with stone solved the problem, as the water was finding it's way in from three sides and not up through the concrete base.

no sure its moisture coming up thro the ground as you can see the patches on the ground. Height of garage floor is about same as front entrance, but is 2" lower at rear entrance of garage to rear garden.

gmgmgm

While it looks damp, does the dampness really cause a problem?

Tucker

I am guessing it's not attached to the house?

Ideally, the garage floor need to be higher all round than the ground around it and my guess this is the real problem, not the absence of a DPM under the base.

You mention the walls also are damp. So, if you raise the floor, it's unlikely to stop the walls from being damp?

I think the best bet and cheapest is to dig out around the garage, fill with limestone and reduce the moisture gathering on the perimeter of the brickwork.

mutley74

Tucker wrote: »

I am guessing it's not attached to the house?

Ideally, the garage floor need to be higher all round than the ground around it and my guess this is the real problem, not the absence of a DPM under the base.

You mention the walls also are damp. So, if you raise the floor, it's unlikely to stop the walls from being damp?

I think the best bet and cheapest is to dig out around the garage, fill with limestone and reduce the moisture gathering on the perimeter of the brickwork.

Garage is on side of house. We only get dampness at patches in the walls, mainly at an internal pillar which we are hoping to get removed (to make more room).