ᐅ What is the height of my knee wall?

Created on: 18 Feb 2014 13:09
D
delf
Hello!

We are planning a single-family house on a nice plot of land.

The basic requirements for the house on the plot are:

- Maximum one-story construction
- Gable roof with a 30-degree pitch
- Allowed eaves height 5 m (16 feet)
- Allowed ridge height 9 m (30 feet)

How high is / can / must my knee wall be?
D
delf
19 Feb 2014 10:12
What’s going on here?

As you can read, this is completely new territory for me.

The plot is 691 m2 (7435 sq ft) with a slope of about 1 m (3 ft).

The house currently measures 10 x 12.5 m2 (33 x 41 ft).

Kind regards
D
delf
19 Feb 2014 10:14
The height of the ground floor should be standard/normal. No extra height.
E
E.Curb
19 Feb 2014 10:53
Hello,
then just do it the way the Doc described: mark it out and measure it.

Best regards
D
delf
20 Feb 2014 09:08
Once you know how to do it, it’s definitely quite simple.
D
Doc.Schnaggls
20 Feb 2014 09:23
Hello Delf,

I’ll try to explain it clearly:

First, draw the side wall (width x height) of the ground floor, above which the roof ridge is located.

Then, mark the thickness of the ceiling on the wall as a “beam.”

In the middle of the wall, draw a line upward that is 9 meters (30 feet) long to scale – this represents your maximum ridge height.

At that point, draw your roof slopes with an angle of 30° each, extending these lines beyond the ground floor wall to the right and left.

Next, extend the outer edges of your ground floor wall upward until they intersect with the roof lines.

Then, you just need to measure the length of the line from this intersection point to the top edge of your ground floor ceiling – this will give you your knee wall height.

Best regards,
Dirk

PS: You also need to ensure the eave height is not exceeded – for this, simply add the knee wall height to the ground floor height (including the ceiling) and consider the 5 meters (16 feet) you mentioned.
D
Doc.Schnaggls
20 Feb 2014 10:33
ypg schrieb:
But then it results in a second full storey – the requirement is a single-storey design...!

I don’t see it that way.

Even if I take the top edge of the basement ceiling or the floor slab as the lower reference point, I initially have a storey height of at least about 2.70 m (8 ft 10 in), plus the thickness of the intermediate ceiling of about 0.40 m (16 inches), which already adds up to 3.10 m (10 ft 2 in). Then there are still 1.90 m (6 ft 3 in) remaining up to the maximum eaves height of 5.0 m (16 ft 5 in).

From this 1.90 m (6 ft 3 in), subtracting the thickness of the roof (about 0.30 – 0.40 m (12 – 16 inches)) leaves a knee wall height of maximum 1.50 – 1.60 m (5 ft – 5 ft 3 in).

For me, that no longer counts as a full storey.

Regards,

Dirk