ᐅ Foundation for an Extension: Is This the Right Approach? Any Experiences?
Created on: 10 Jun 2012 23:49
H
Huti
Hello.
This is my first post here, so I’ll include a brief introduction.
My name is Stefan, I’m 31 years old, and I recently bought a house built in 1951. I am currently renovating and remodeling it.
Although I’m not a professional (trained as a business administrator, not a tradesperson), I’m doing a lot of the work myself during the renovation.
Right now, I’m gathering information for a planned extension at the front of the house (the main entrance will be enlarged / extended outward by 1.5m (5 feet) and the front door will be rotated 90°).
I’ll describe how I have planned this construction project so far and would appreciate advice on whether this is correct or how it might be better / more practical / feasible at all.
As I mentioned, I’m not a professional, so please excuse any missing technical terms or often amateurish expressions.
The extension itself is planned to be 1.5m (5 feet) deep and 3.5m (12 feet) wide, with the front door located on the short side at a 90° angle to the usual front of the house.
The main entrance (now and in the future) is about 50cm (20 inches) above ground level and is reached by 3 steps.
The structure will be built with aerated concrete blocks or Poroton blocks, 17.5cm (7 inches) thick.
For the foundation, a trench 80cm (31 inches) deep will be dug around the outside and filled with concrete to ensure frost protection.
Here is my first specific question: Is it sufficient to build this foundation up to ground level and then build the walls on top (with appropriate moisture protection), or should the foundation be cast significantly above ground level using formwork? Possibly even the full 50cm (20 inches) that will need to be backfilled later?
How should the connection to the existing house and basement wall be made? Should it simply be concreted together (“cast in place”) or is a moisture barrier required between the basement wall and the foundation for the extension?
Of course, it is clear that insulation is necessary at the transition to the outside (toward the soil).
The 50cm (20 inches) above ground to match the house entrance level will be filled with construction rubble. Above this, screed, underfloor heating, top screed, and tiles will be installed (the same continuous flooring as in the adjacent hallway extended by the new extension). Any objections?
I hope I have explained my project clearly, and even if my planning is misguided, I kindly ask for well-intentioned advice.
Thanks in advance and best regards
This is my first post here, so I’ll include a brief introduction.
My name is Stefan, I’m 31 years old, and I recently bought a house built in 1951. I am currently renovating and remodeling it.
Although I’m not a professional (trained as a business administrator, not a tradesperson), I’m doing a lot of the work myself during the renovation.
Right now, I’m gathering information for a planned extension at the front of the house (the main entrance will be enlarged / extended outward by 1.5m (5 feet) and the front door will be rotated 90°).
I’ll describe how I have planned this construction project so far and would appreciate advice on whether this is correct or how it might be better / more practical / feasible at all.
As I mentioned, I’m not a professional, so please excuse any missing technical terms or often amateurish expressions.
The extension itself is planned to be 1.5m (5 feet) deep and 3.5m (12 feet) wide, with the front door located on the short side at a 90° angle to the usual front of the house.
The main entrance (now and in the future) is about 50cm (20 inches) above ground level and is reached by 3 steps.
The structure will be built with aerated concrete blocks or Poroton blocks, 17.5cm (7 inches) thick.
For the foundation, a trench 80cm (31 inches) deep will be dug around the outside and filled with concrete to ensure frost protection.
Here is my first specific question: Is it sufficient to build this foundation up to ground level and then build the walls on top (with appropriate moisture protection), or should the foundation be cast significantly above ground level using formwork? Possibly even the full 50cm (20 inches) that will need to be backfilled later?
How should the connection to the existing house and basement wall be made? Should it simply be concreted together (“cast in place”) or is a moisture barrier required between the basement wall and the foundation for the extension?
Of course, it is clear that insulation is necessary at the transition to the outside (toward the soil).
The 50cm (20 inches) above ground to match the house entrance level will be filled with construction rubble. Above this, screed, underfloor heating, top screed, and tiles will be installed (the same continuous flooring as in the adjacent hallway extended by the new extension). Any objections?
I hope I have explained my project clearly, and even if my planning is misguided, I kindly ask for well-intentioned advice.
Thanks in advance and best regards
Not publishing a DIY guide is, first, understandable and, second, not what was asked for. The well-intentioned tip was nice and sensible—that’s not the issue. But why then start pretending with pages of follow-up questions instead of simply giving brief, concrete reasons why this must be inspected on-site or explaining which site-specific conditions are important, missing, or cannot be specified (which still hasn’t happened)?
Since you were not even willing to answer the simplest questions about the foundation’s construction—bearing in mind that given the level of these questions (from someone who, after all, “has no clue”) it doesn’t matter whether I intend to build an extension, a garden shed, or a doghouse—the same question arises: why then the long string of questions? Just for the pitiful attempt to “expose” someone who has already admitted to being a layperson as exactly that, and to show them their lack of knowledge (quote: “I didn’t expect you to really be able to answer these questions”)?
At least BratacDD has shown that well-meant advice and helpful answers can be combined with the actual question asked… if you want to. And as is generally known—and already mentioned here—the actual execution of the construction project requires a building permit / planning permission anyway, so why the panic?
Sorry, but to me this behavior is incomprehensible and does not correspond to normal, respectful interaction. After all, participation in a forum like this is voluntary (just a tip for you—I don’t want to leave anything undone here).
Since you were not even willing to answer the simplest questions about the foundation’s construction—bearing in mind that given the level of these questions (from someone who, after all, “has no clue”) it doesn’t matter whether I intend to build an extension, a garden shed, or a doghouse—the same question arises: why then the long string of questions? Just for the pitiful attempt to “expose” someone who has already admitted to being a layperson as exactly that, and to show them their lack of knowledge (quote: “I didn’t expect you to really be able to answer these questions”)?
At least BratacDD has shown that well-meant advice and helpful answers can be combined with the actual question asked… if you want to. And as is generally known—and already mentioned here—the actual execution of the construction project requires a building permit / planning permission anyway, so why the panic?
Sorry, but to me this behavior is incomprehensible and does not correspond to normal, respectful interaction. After all, participation in a forum like this is voluntary (just a tip for you—I don’t want to leave anything undone here).