Hello everyone,
We are about to underpin two basement rooms with a contractor. The ceiling height is planned to be increased from 2.15 m (7 ft) to about 2.65 m (8.7 ft). Our structural engineer mentioned that if the strip foundation extends 80 cm (31.5 inches) below the current basement floor, underpinning the basement walls might not be necessary. We have now excavated a small area and found that the strip foundation is only 30 cm (12 inches) deep.
This means we will have to underpin the entire structure step by step. (We are still waiting for the structural engineer’s detailed instructions.) In principle, this will probably result in something like in my sketch:
The contractor has provided an offer for the floor build-up consisting of 15 cm (6 inches) concrete with reinforcement, 10 cm (4 inches) insulation, and gravel. For underpinning, the contractor will likely use waterproof concrete and steel cages.
I have the following questions:
We are about to underpin two basement rooms with a contractor. The ceiling height is planned to be increased from 2.15 m (7 ft) to about 2.65 m (8.7 ft). Our structural engineer mentioned that if the strip foundation extends 80 cm (31.5 inches) below the current basement floor, underpinning the basement walls might not be necessary. We have now excavated a small area and found that the strip foundation is only 30 cm (12 inches) deep.
This means we will have to underpin the entire structure step by step. (We are still waiting for the structural engineer’s detailed instructions.) In principle, this will probably result in something like in my sketch:
The contractor has provided an offer for the floor build-up consisting of 15 cm (6 inches) concrete with reinforcement, 10 cm (4 inches) insulation, and gravel. For underpinning, the contractor will likely use waterproof concrete and steel cages.
I have the following questions:
- There is a strong damp smell in the basement. The exterior basement area will also be excavated and insulated soon, so at least from the outside we should be “safe.” What additional measures could be taken during underpinning to protect the floor against moisture as well? I would like to avoid the basement walls absorbing moisture from below if possible. The contractor believes that due to the hillside location, water or moisture will not be a problem. However, I would still like to inform myself rather than trust blindly.
- Should I request a specific type of insulation, since the offer only mentions “10 cm insulation”?
Anyone have any ideas or tips?
The builder said that a drainage system would be installed under the slab and then routed outward. By the way, after we dug down a bit, I noticed a small puddle of water in a small area (more towards the center of the house rather than near the exterior walls). It looks like there are larger stones or very hard clay around it that seems to be "sweating."
The builder said that a drainage system would be installed under the slab and then routed outward. By the way, after we dug down a bit, I noticed a small puddle of water in a small area (more towards the center of the house rather than near the exterior walls). It looks like there are larger stones or very hard clay around it that seems to be "sweating."
Similar topics