Hello,
I am currently planning a new build (my first), which is intended to have 2-3 residential units and will likely aim for an energy efficiency rating of 40+. Essentially, it could be called a multi-generational house. Initially, only 2 units will be developed (one on the ground floor and one on the upper floor), but in the future, a third unit is planned for the attic. I would like to leave the attic unit as a shell at first, but have all the connections, wiring, and so on installed. The goal is to avoid any further construction work later so that it can be used as a separate unit.
As far as I know, a separate residential unit requires the following conditions:
- Its own lockable entrance
- Its own electricity meter
- One kitchen connection each
- One bathroom connection each (toilet and shower)
I hope I haven’t missed anything here. If so, please let me know.
Now to my question: To plan a bit better, I would like to get an idea of how much an additional residential unit costs in terms of installing connections for an extra kitchen and an additional bathroom, as well as setting up a separate electrical circuit with its own electricity meter in the utility room. In other words, the extra costs you should budget for when turning a standard single-family house into a house with 2 or 3 units.
For now, I am only interested in the cost of the connections—that is, the potential for an additional unit—not the cost of the kitchen or bathroom fixtures themselves.
I hope you can help. Many thanks in advance for any comments and explanations!
I am currently planning a new build (my first), which is intended to have 2-3 residential units and will likely aim for an energy efficiency rating of 40+. Essentially, it could be called a multi-generational house. Initially, only 2 units will be developed (one on the ground floor and one on the upper floor), but in the future, a third unit is planned for the attic. I would like to leave the attic unit as a shell at first, but have all the connections, wiring, and so on installed. The goal is to avoid any further construction work later so that it can be used as a separate unit.
As far as I know, a separate residential unit requires the following conditions:
- Its own lockable entrance
- Its own electricity meter
- One kitchen connection each
- One bathroom connection each (toilet and shower)
I hope I haven’t missed anything here. If so, please let me know.
Now to my question: To plan a bit better, I would like to get an idea of how much an additional residential unit costs in terms of installing connections for an extra kitchen and an additional bathroom, as well as setting up a separate electrical circuit with its own electricity meter in the utility room. In other words, the extra costs you should budget for when turning a standard single-family house into a house with 2 or 3 units.
For now, I am only interested in the cost of the connections—that is, the potential for an additional unit—not the cost of the kitchen or bathroom fixtures themselves.
I hope you can help. Many thanks in advance for any comments and explanations!
Felix85 schrieb:
What can I plan myself to design multiple residential units as cost-effectively as possible?It is best to hire an architect who has experience with this type of building. The draftsman of a general contractor is not suitable for this.
Bathroom above bathroom, kitchen above kitchen saves costs and simplifies planning.
Connections sometimes run through empty conduits.
Insulation, windows, dormers for might maybe possibly are expensive.
Parking spaces usually 2 per dwelling unit, not one behind the other.
Are 3 dwelling units allowed?
What does the floor area ratio and the floor space index say?
Connections sometimes run through empty conduits.
Insulation, windows, dormers for might maybe possibly are expensive.
Parking spaces usually 2 per dwelling unit, not one behind the other.
Are 3 dwelling units allowed?
What does the floor area ratio and the floor space index say?
haydee schrieb:
Bathroom over bathroom, kitchen over kitchen saves costs and makes planning easier. Alright, many thanks, I can take that into account in the preliminary planning.
haydee schrieb:
Insulation, windows, dormers might possibly be expensive. Insulation will definitely be a costly factor (for 40 plus). So far, I have planned the windows as recommended by an architect for a passive house (mostly windows on the south and west sides with external blinds to control heat gain, fewer on the other sides). The architect will certainly make adjustments, but for now, I am only preparing a draft so he has something to work with. Dormers or decorative elements on the exterior walls are not planned. The floor plan is square, topped with a hip roof.
haydee schrieb:
Usually 2 parking spaces per housing unit, not in tandem. That would really be quite demanding. In a quick search yesterday, I found figures closer to 0.6 to 0.8 parking spaces per unit. But since requirements vary greatly depending on the municipality, this will definitely be an important point to clarify.
haydee schrieb:
What about floor area ratio and site coverage ratio? Site coverage ratio 0.4, floor area ratio 1.0. Both should not be a problem.
hanse987 schrieb:
Best to hire an architect experienced with this type of house. A draftsman from a general contractor is not suitable. Absolutely! I believe I have a good one with plenty of experience, who has also built multi-family and multi-generation houses. He also has experience with 40 plus projects (which was harder to find than expected), so I’m optimistic.
I have a question about the roof, although it’s basically off-topic here. If this is not the right place, I can open a separate thread for it.
Insulating a roof is said to be significantly more expensive than a simple ceiling.
Do you have a rough estimate of how much more the insulation costs?
And could I reasonably avoid this by adding another ceiling in the attic (e.g., at 2.4m (8 feet)), so I wouldn’t have to insulate all the way up to the roof ridge? Then there would also be an unconditioned cavity above, which I've read can help with insulation as well.
Felix85 schrieb:
Square floor plan with a pyramidal roof on top. Felix85 schrieb:
From a planning perspective, a third living unit is intended to be added later (attic). I would like to keep the attic as a shell for now but already have all the connections, wiring, etc., installed. Felix85 schrieb:
Insulating a roof is supposed to be significantly more expensive than insulating a regular ceiling.
Do you have a rough estimate of how much more expensive roof insulation is? A pyramidal roof contradicts the concept of an attic.
With a pyramidal roof, you are essentially building a three-story building, but the pyramidal roof is constructed as a cold roof, which does not allow for a habitable space.
ypg schrieb:
A hip roof contradicts with an attic.Is that really the case? I have currently planned it with a pitch between 30-35 degrees. This still provides significant living space when converted, which would be enough for a child’s apartment (especially during the first approximately 5-10 years while attending training or university).ypg schrieb:
With a hip roof, you’re essentially building a three-story house; the hip roof is then constructed as a ventilated roof, so you can’t have living space there.Is “ventilated roof” the correct term for what I previously described as a “hollow space for insulation”? That’s my question: Is that kind of roof structure absolutely necessary? Would it make sense to limit the ceiling height within the hip roof to 2.4 m (7 ft 10 in) so that the peak remains a ventilated roof? Or from a cost perspective, does it make no difference whether you install an additional ceiling in the attic or insulate all the way up to the ridge?tomtom79 schrieb:
Especially, how is the stairwell supposed to work?The stairwell is designed so that each apartment is accessed through a lockable door. Why would that be a problem in the attic? There, the staircase also ends at a lockable door.Similar topics