ᐅ A genuine two-family house with similarly sized living areas
Created on: 13 May 2021 16:44
C
CleoBau
Hello everyone,
First, our objectives and the facts, followed by our questions. We look forward to your feedback :-)
Thank you very much.
Objectives:
A two-family house designed for families with maximum functional use; optimal utilization of living space on the plot and adherence to the building regulations; equal living conditions for both households regarding natural light (south-facing living rooms, light wells for the basement) and comfort; compliance with KfW40 energy efficiency standards.
Building Regulations / Restrictions
Plot size: 810 m² (18x45 m (59x148 feet), rectangular, narrow side facing the street and aligned north/south; no trees, shrubs, etc.)
Neighboring buildings: Detached houses
Terrain: flat, no slope
Site coverage ratio (/building footprint ratio): 0.2, with a possible extension “up to a site coverage ratio of 0.5”
Floor area ratio: 0.4
Building envelope: 12x40 m (39x131 feet); building line and boundary: minimum 5.0 m (16 feet) distance between public road and main building or garages, and 3.0 m (10 feet) to every neighboring plot; maximum footprint of 120 m² (1,292 sq ft)
Edge development: no specification
Number of parking spaces: no specification
Number of floors: 2 full stories
Roof type: no requirement; in the street there are mansard roofs, gable roofs, hip roofs, and gambrel roofs
Architectural style: none specified; houses in the street vary from Italian-style cottages to brick bungalows
Orientation: not specified
Maximum heights / limits: base height max. 0.80 m (2.6 feet); eaves height max. 4.30 m (14 feet); ridge height max. 8.80 m (29 feet) measured to the nearest manhole cover (approximately standard curb depth, around 20 cm (8 inches))
Other requirements: tree planting on the plot, currently not relevant for the building design
Client Requirements
Style, roof type, building type: none specified, preferably mansard roof for better use of the attic
Basement, floors: fully finished and usable basement + 2 full stories + attic
Number of people, age group: 2 families with 1–3 children each
Space requirements on ground and upper floors: 120–140 m² (1,292–1,507 sq ft) per apartment
Guest rooms per year: one guest room per unit would be nice
Open or closed design: open design (3 m (10 feet) boundary to neighbor’s plot must be respected on both sides, if that is what is meant)
Conservative or modern design: target is KfW40, solid construction (not prefab)
Open kitchen, kitchen island: currently undecided
Number of dining places: 6–8 people
Fireplace: no, not planned
Balcony, roof terrace: terrace for one unit and balcony for the other
Garage, carport: double garage + 2 open parking spaces (possibly carport?) with electric vehicle charging stations
Other: no specific ideas yet, starting with what is feasible within the framework conditions
House Design
Who created the plan: self-made using Roomsketcher
What do you like and why?: large sliding doors from kitchen to living room to create a kind of open plan kitchen/living area, but can be closed to avoid cooking smells; bathrooms about 10 m² (108 sq ft) each for comfortable size; lower apartment should be barrier-free
What do you dislike and why?: staircase on the 1st floor to attic intrudes into the guest room, which is somewhat inconvenient
Cost estimate by architect/planner: I estimate about 520,000 €
Preferred heating technology: ground-source heat pump
If you had to give up on something, which details or extensions
- Could give up: mansard roof if the required two apartments with approx. 120 m² each can be achieved otherwise
- Cannot give up: 2 apartments with at least 4 rooms each
Why is the design as it is now?
Objective: We reviewed floor plans of prefab houses and based ours on those and our current apartment.
What is the most important/basic question regarding the floor plan in 130 characters?
Is my assumption about the site coverage ratio and building regulations correct?
Our questions:
Images attached:
First, our objectives and the facts, followed by our questions. We look forward to your feedback :-)
Thank you very much.
Objectives:
A two-family house designed for families with maximum functional use; optimal utilization of living space on the plot and adherence to the building regulations; equal living conditions for both households regarding natural light (south-facing living rooms, light wells for the basement) and comfort; compliance with KfW40 energy efficiency standards.
Building Regulations / Restrictions
Plot size: 810 m² (18x45 m (59x148 feet), rectangular, narrow side facing the street and aligned north/south; no trees, shrubs, etc.)
Neighboring buildings: Detached houses
Terrain: flat, no slope
Site coverage ratio (/building footprint ratio): 0.2, with a possible extension “up to a site coverage ratio of 0.5”
Floor area ratio: 0.4
Building envelope: 12x40 m (39x131 feet); building line and boundary: minimum 5.0 m (16 feet) distance between public road and main building or garages, and 3.0 m (10 feet) to every neighboring plot; maximum footprint of 120 m² (1,292 sq ft)
Edge development: no specification
Number of parking spaces: no specification
Number of floors: 2 full stories
Roof type: no requirement; in the street there are mansard roofs, gable roofs, hip roofs, and gambrel roofs
Architectural style: none specified; houses in the street vary from Italian-style cottages to brick bungalows
Orientation: not specified
Maximum heights / limits: base height max. 0.80 m (2.6 feet); eaves height max. 4.30 m (14 feet); ridge height max. 8.80 m (29 feet) measured to the nearest manhole cover (approximately standard curb depth, around 20 cm (8 inches))
Other requirements: tree planting on the plot, currently not relevant for the building design
Client Requirements
Style, roof type, building type: none specified, preferably mansard roof for better use of the attic
Basement, floors: fully finished and usable basement + 2 full stories + attic
Number of people, age group: 2 families with 1–3 children each
Space requirements on ground and upper floors: 120–140 m² (1,292–1,507 sq ft) per apartment
Guest rooms per year: one guest room per unit would be nice
Open or closed design: open design (3 m (10 feet) boundary to neighbor’s plot must be respected on both sides, if that is what is meant)
Conservative or modern design: target is KfW40, solid construction (not prefab)
Open kitchen, kitchen island: currently undecided
Number of dining places: 6–8 people
Fireplace: no, not planned
Balcony, roof terrace: terrace for one unit and balcony for the other
Garage, carport: double garage + 2 open parking spaces (possibly carport?) with electric vehicle charging stations
Other: no specific ideas yet, starting with what is feasible within the framework conditions
House Design
Who created the plan: self-made using Roomsketcher
What do you like and why?: large sliding doors from kitchen to living room to create a kind of open plan kitchen/living area, but can be closed to avoid cooking smells; bathrooms about 10 m² (108 sq ft) each for comfortable size; lower apartment should be barrier-free
What do you dislike and why?: staircase on the 1st floor to attic intrudes into the guest room, which is somewhat inconvenient
Cost estimate by architect/planner: I estimate about 520,000 €
Preferred heating technology: ground-source heat pump
If you had to give up on something, which details or extensions
- Could give up: mansard roof if the required two apartments with approx. 120 m² each can be achieved otherwise
- Cannot give up: 2 apartments with at least 4 rooms each
Why is the design as it is now?
Objective: We reviewed floor plans of prefab houses and based ours on those and our current apartment.
What is the most important/basic question regarding the floor plan in 130 characters?
Is my assumption about the site coverage ratio and building regulations correct?
Our questions:
- Site coverage ratio: Plot area 810 m² (8,715 sq ft) with a site coverage ratio of 0.2 (=162 m² (1,743 sq ft)); limit: footprint for single-family house max. 120 m² (1,292 sq ft). What can be included in the remaining 42 m² (452 sq ft) difference (balconies, bay windows, light wells, courtyards, terraces…)?
- Extended site coverage ratio: for garages, etc., “site coverage ratio may be exceeded up to 0.5.” How is this calculated? Half of the plot area (405 m² (4,359 sq ft)), half of the plot area minus the original site coverage (405–162 = 243 m² (2,616 sq ft)), half of the site coverage ratio (81 m² (872 sq ft)), or half the footprint of the house (60 m² (646 sq ft))?
- How are light wells (planted embankments, not attached cellar shafts) for basement illumination counted, under site coverage ratio or extended site coverage ratio?
- How are balconies and overhanging bay windows counted?
- What wall thicknesses should we expect for exterior walls (KfW40 standard with brick veneer) and interior walls?
Images attached:
H
hanghaus200014 May 2021 08:19CleoBau schrieb:
Maximum Heights/Limitations: Foundation height max. 0.80 m (31 inches); eave heights max. 4.30 m (14 feet); ridge heights max. 8.80 m (29 feet) measured from the nearest manhole cover (which is approximately at standard curb depth, about 20 cm (8 inches)?)
Other requirements: Tree planting on the property, initially not relevant for the building
Client Requirements
Architectural style, roof shape, building type: none specified, preferably a mansard roof for better use of the attic space
Basement, floors: fully finished and usable basement + 2 full floors + atticAn eave height of 4.30 m (14 feet) does not accommodate 2 full floors. Two times 3 m (10 feet) equals 6 m (20 feet).
A ridge height of 8.80 m (29 feet) does not allow for 3 stories. Three times 3 m (10 feet) would be 9 m (30 feet), and that doesn’t even include the roof pitch.
This would allow for a 1.5-story duplex with about 1.3 m (5 feet) knee wall. You might want to look for examples of such models with first-time home builders.
Your current plan won’t fit within these height limits.
Talk to the bank again about getting a higher loan amount.
Do you already have the plot of land?
H
hanghaus200014 May 2021 08:36What does the zoning plan say about roof extensions? Are semi-detached houses allowed, and what about boundary developments with garages or carports?
Regarding the budget once again. Depending on the construction location, you can expect around 2000 - 2500 euros per square meter for standard finishes, excluding additional construction costs (such as planning permission/building permit fees), exterior landscaping, garage or carport, and interior fittings including the kitchen. A price of 2000 euros per square meter will no longer be achievable in most parts of Germany without significant self-labor and support from friends in skilled trades. By the time you actually start building, quite some time will have passed, and prices will not have decreased.
In your cost estimate, for example, the basement is significantly undervalued. It is supposed to be at least partially finished as living space and is fully within the thermal envelope, so why should it be this cheap? There are good reasons why many houses today are built without basements.
Without knowing the construction site or how much self-labor is involved, and assuming approximately 350 square meters (I haven’t precisely calculated the design’s exact floor area), I estimate the costs as follows:
2000 x 350 = 700,000 euros
Additional construction costs including excavation 50,000–60,000 euros
Exterior landscaping 30,000 euros
Garage/carport 10,000–30,000 euros (depending on what is chosen)
Kitchen/interior fittings at least 15,000 euros
In the end, this is just like building two stacked houses, so it will cost a bit less than two semi-detached houses.
I recommend reading up on the development of building material prices. There are now articles about this topic in almost every daily newspaper.
In your cost estimate, for example, the basement is significantly undervalued. It is supposed to be at least partially finished as living space and is fully within the thermal envelope, so why should it be this cheap? There are good reasons why many houses today are built without basements.
Without knowing the construction site or how much self-labor is involved, and assuming approximately 350 square meters (I haven’t precisely calculated the design’s exact floor area), I estimate the costs as follows:
2000 x 350 = 700,000 euros
Additional construction costs including excavation 50,000–60,000 euros
Exterior landscaping 30,000 euros
Garage/carport 10,000–30,000 euros (depending on what is chosen)
Kitchen/interior fittings at least 15,000 euros
In the end, this is just like building two stacked houses, so it will cost a bit less than two semi-detached houses.
I recommend reading up on the development of building material prices. There are now articles about this topic in almost every daily newspaper.
H
hanghaus200014 May 2021 08:58This could be a fair division.
Thank you for your feedback.
The development plan cannot be linked. It is 27a and area W2 of Teltow (Brandenburg).
Why does a development plan allow 2 full stories if this can never be achieved with the permitted eaves height?
Semi-detached houses are not allowed on one plot, only one half each. Statement from the building authority: "A two-family house is possible with a shared entrance." We will revise our plans accordingly.
I will ignore the personal remarks. Welcome to the world where inexperienced people also write in forums to ask for help.
The development plan cannot be linked. It is 27a and area W2 of Teltow (Brandenburg).
Why does a development plan allow 2 full stories if this can never be achieved with the permitted eaves height?
Semi-detached houses are not allowed on one plot, only one half each. Statement from the building authority: "A two-family house is possible with a shared entrance." We will revise our plans accordingly.
I will ignore the personal remarks. Welcome to the world where inexperienced people also write in forums to ask for help.
CleoBau schrieb:
Welcome to the world where inexperienced people also write in a forum to ask for help.However, the inexperienced person should also read the statements about impracticality and not overlook them. Before correcting the advisor’s suggestions and refusing to believe them, it is important to think it through and possibly ask questions. Ignoring facts no longer works on page 3 of a forum... in real life, you would have an unfinished building shell.Similar topics