Hello, I'm in the planning and calculation stage for a future extension of about 35-40 square meters. I've been thinking of making the foundation using the pier type, but instead of piers, using steel piles that are driven down to bedrock and protrude about 0.5m. On these, I plan to place wooden beams or steel beams as the main support beam, then floor joists on top of that. The pros and cons of each variant seem to be that wood is cheaper but builds more height, whereas steel beams are convenient as they can simply be welded to the piles. What about load-bearing capacity, how can I calculate the sizes I need, and the distance between the beams and attachment to the piles? What do you think of this foundation type?
I want it elevated because there is a basement in the house and I want the floors to be at the same level. Additionally, it's easy to inspect underneath, and a crawl space seems to pose a moisture risk. And since I work with foundation laying/piling, I want to take advantage of that knowledge at home as well
I want it elevated because there is a basement in the house and I want the floors to be at the same level. Additionally, it's easy to inspect underneath, and a crawl space seems to pose a moisture risk. And since I work with foundation laying/piling, I want to take advantage of that knowledge at home as well
I am also going to build a house on a completely open pillar foundation directly on rock. Preferably steel piles or beams. Mine will be screwed into the rock or onto a concrete block. I am searching to find suppliers for this but I must be writing completely crazy things because I seem to end up in the wrong place... Have you found any supplier?
The supplier of steel piles will be through the company I work at. The steel beam will probably be second-hand, or from Stena, Tibnor, or similar, once I know the size I need.
Edit: if you’re building directly on rock, it must be easier to drill holes and cast reinforcement in the rock, and then continue up with concrete pillars. I only have old seabed/real bad clay on my property, so I have to pile about 15 meters down to rock/hard moraine.
Edit: if you’re building directly on rock, it must be easier to drill holes and cast reinforcement in the rock, and then continue up with concrete pillars. I only have old seabed/real bad clay on my property, so I have to pile about 15 meters down to rock/hard moraine.
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Member
· Västra Götealand
· 154 posts
Are you not worried that the new foundation with support piles will be a bit "too good" compared to the existing foundation under the house you are expanding? Or is it also piled?
It is clear that the risk exists, in the worst case one has to underpin existing buildings with piles, it is compensation founded with a basement. So there are definitely more fun jobs.
Do not want a basement in the new part, mostly from an economic and time perspective.
Do not want a basement in the new part, mostly from an economic and time perspective.
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Member
· Västra Götealand
· 154 posts
At that point, I had excavated and foundationed the new section with foam insulation or Leca. It must be cheaper than piling both the new and old sections.
Have been thinking a bit more about different foundation methods, and possible settlement movements on the old house, the current house was built in '52 and I drained it 2 years ago, there was only about a 1cm wide crack in one corner, on the opposite side of the house where I plan the extension. And it was most likely due to the garage driveway into the basement there, with a frozen drain as a result. But judging from that, I think the house is "stable"? If you now make an extension with, piled pier foundation or slab on grade, and only nail attachment between the new and old frame, that allows a little movement? Or am I thinking wrong?