MrtnBuilder

We don't need access to the roof from the inside. I'm more interested in whether it's possible to combine it with a hipped roof and how to do it correctly without sacrificing the height of the rooms underneath. In Poland, flat roofs are among the more expensive roofs due to the lack of knowledge and fear of installing this solution. But in my situation, where the maximum building height is fixed, this is probably the only possible solution?

The administration allows a maximum of two floors in a building, so if we already have two floors, even the side part of the mansard roof is unfortunately counted as a roof. Unfortunately, in Poland, such situations are not easily resolved by the authorities. Our officials usually don't help the investor, quite the opposite. In Poland, to obtain a building permit, you must submit three volumes of documents, each usually over 100 pages long, and the wait for a decision often exceeds a year. In this situation, I have no other ideas for this roof; I don't think I can simply build this house. I tried to combine several hipped roofs in Revit to reduce the final ridge height, but I don't know how to combine them properly, I don't even know if it's possible to combine such roofs with a rectangular shape.

I was thinking about a mansard roof, but from what I've read, the first part of a mansard roof has a high pitch, often 50-60 degrees, and unfortunately, in my case, only a pitched roof with a pitch of 30-45 degrees is permitted. Does a mansard roof that only covers this range make sense? Is it even possible to create such a roof with only this pitch? The building authorities also state that flat roofs with pitches of up to 10 degrees are permitted, but they can be used on a maximum of 50% of the roof surface. Unfortunately, the problem with this roof is that I don't know how I could connect it to a hipped roof. In this case, the hipped roof wall would have to be higher to extend the membrane from the flat roof to the hipped roof wall. In this situation, would the height of the rooms above the hipped roof have to be even greater? Because if the flat roof is lower, there will again be a problem with the height of the rooms under this roof

In this difficult situation, is there any other option to divide this hipped roof into several smaller sections, which would allow for a lower height to the ridge? Unless dividing the roof would require the roof to be constructed individually, rather than using prefabricated trusses? In that case, I'm not sure it makes sense to do it at all, as the roof would be extremely expensive if the prefabricated trusses had to be abandoned

That's exactly what they came up with, which isn't very smart because the foundation should be slightly higher. In my case, the ground is sandy, so it's only 10 centimeters lower than the entrance to the building, but there will also be a terrace on the ground, so the design shows that the ground is level with the entrance to the building, therefore the ground and the entrance to the building are at the same height.

The plan I attached at the beginning included truss beams. Unfortunately, intermediate beams supporting the ceiling must run beneath these beams (these are the beams shown on the plan as dashed lines), so I'm not sure if it makes sense to do this, since I'll have to lower the ceiling anyway to accommodate the beams supporting the trusses. Another option was to place the supporting beams directly into the truss, but in that case, it would block the access to the utilities. I don't know what to do in this situation. After the company stole my money, I'm left to my own devices and don't know how to handle all this. I encounter problems with every solution. I'm starting to doubt whether this building can even be built given the 950-centimeter maximum height

Unfortunately, in Poland, the building height is measured from the lowest point of the building entrance to the roof ridge, including the roof finishing layers. Regarding the roof height, assuming I'm 30-40 centimeters short, I would have to lower both rooms by 20 centimeters. Unfortunately, I don't know why, but I have a ceiling joist in every significant place where ventilation ducts could be passed through, so after talking to the contractors, they said I would need to lower the ceiling. It's also possible that sewage pipes would be required in some places in the ceiling, so the room height is such that we don't have to worry about the height of the building and the rooms. Regarding the sewage system, it's possible that a ceiling passage will be required because the design was changed after the sewage system and foundation slab were installed. Unfortunately, we had to terminate the contract with the company that was supposed to build the building due to constant delays. They then stole the money we paid for the materials and fled the construction site. We had to change the design to be able to financially continue the investment, hence the extra height in the rooms.

the height of the rooms is 290 centimeters because we intend to install a mechanical ventilation system and install beams in the suspended ceilings, after lowering 20 centimeters for the installation, there will be 270 centimeters of clear height in each room.

Thank you very much for your answer. With a single hipped roof, as you wrote, the height will be 343 centimeters. Assuming the rooms are 290 centimeters each: (290 + 290 + 342) = 922 centimeters. Assuming we have 922 centimeters, it will be difficult to fit the ceiling between the floors and the roof finishing layers. The ceiling between the floors will be approximately 40 centimeters (a wooden ceiling with acoustic insulation layers and underfloor heating on the first floor). In this situation, after adding 40 centimeters, we have a total of 962 centimeters without the roof finishing layers. Unless I'm miscalculating and misunderstanding something? In this situation, unfortunately, the roof would be 30 centimeters higher than the administrative requirements, which state that the maximum height of the building cannot exceed 950 centimeters. Is there any way to divide the hipped roof into smaller sections, which would reduce the roof span and its height to the ridge? Thank you again for your help.

Hi, According to the administrative decision, we must have a pitched roof with a slope of between 30 and 45 degrees. The roof surfaces can have different slopes; it's important that they are within the 30-45 degree range. We currently have a foundation slab, along with the underfloor heating system and the sewage system. I've marked the sewage outlets with red circles on the ground floor plan. The attached document also includes the floor system design. We can only move the ground floor walls so as not to encroach on the underfloor heating system. As I mentioned, the problem arises with the roof. The building is rectangular in shape with an attached garage. Due to the administrative decision, the building's height, measured from the entrance to the roof ridge, including the roof layers, cannot exceed 950 centimeters. We planned a hipped roof on the building, but it's not possible. Here's why: The building has two floors, each 290 centimeters high. With a total height of 950 centimeters, we're left with 370 centimeters for the roof, including the ceiling between the floors. (290 + 290 = 580) (950 - 580 = 370) The building has a front elevation of 1611 centimeters and a side elevation of 1186 centimeters. We can't create a hipped roof on the building because the facades are too long and the roof is too high. The only solution I came up with was a multi-pitched roof. Unfortunately, I'm not an expert in this field, so I have no idea what such a roof should look like if the entire building, including the roof, was below 950 centimeters. The ground floor drawing shows walls. The elements drawn with dashed lines are beams that could also support the roof. We plan to build a roof using prefabricated trusses. Do you have any ideas on how to solve this problem? Thank you for your help.