How to calculate area of house

prosaic

What do I exclude/include when calculating areas?

I'm looking at Hamilton Park in D15, a new development where show houses are open. The Orpen type area is given as 112 sq.m. on the brochure.

There is no garage or other structure outside the house.

I measured the show house and totalled areas of rooms, hall, landing, under-stairs, stairs, hot-press. I get 106.4 sq.m. which is smaller than brochure's 112 sq.m.

Should I include under-stairs storage? Count the stairs once?

If I total the area based only on external walls (ignoring presence of stairs or of internal walls and such), I get 112.4 sq.m. This is close to what the brochure quotes.

I thought the latter area is used in commercial real estate but not in residential. What is standard practice for residential area? Do estate agents follow standard practice in general? Or what is most usually included/excluded?

wowy

prosaic wrote: »

What do I exclude/include when calculating areas?

I'm looking at Hamilton Park in D15, a new development where show houses are open. The Orpen type area is given as 112 sq.m. on the brochure.

There is no garage or other structure outside the house.

I measured the show house and totalled areas of rooms, hall, landing, under-stairs, stairs, hot-press. I get 106.4 sq.m. which is smaller than brochure's 112 sq.m.

Should I include under-stairs storage? Count the stairs once?

If I total the area based only on external walls (ignoring presence of stairs or of internal walls and such), I get 112.4 sq.m. This is close to what the brochure quotes.

I thought the latter area is used in commercial real estate but not in residential. What is standard practice for residential area? Do estate agents follow standard practice in general? Or what is most usually included/excluded?

Residential floor areas are based on gross internal area, which measures from the internal face of external walls (and so includes halls, stairs, toilets, etc).

Commercial premises will be measured differently (net internal, gross internal, gross external) depending on their use (retail, office, industrial).

Measurement guidelines are set out in the society of chartered surveyors measurement guidelines.

Gumbo

Everything inside the external walls is classed as the floor area.

prosaic

That's great, thanks.
I don't know why I thought it was minus internal walls and such.