| Type | Total | Rooms | Accommodation |
| 24 | 6 | 2 | 1 bedroom, living room |
| 25 | 5 | 5 | 2 bedrooms, living room, study, dining room |
| 26 | 10 | 3 | 1 bedroom, living room, dining area |
| 27 | 2 | 3 | 1 bedroom, living room, dining area |
| 28 | 6 | 3 | 1 bedroom, L-shaped living room, dining area |
| 29 | 6 | 3 | 1 bedroom, L-shaped living room, dining area |
| 30 | 1 | 5 | 2 bedrooms, living room, study, dining room |
| 31 | 15 | 3 | 1 bedroom, living room, dining area |
| 32 | 3 | 3 | 1 bedroom, living room, dining area |
| 33 | 1 | 2 | 1 bedroom, L-shaped living room, roof patio |
| 34 | 1 | 2 | 1 bedroom, L-shaped living room, roof patio |
| 35 | 5 | 5 | 3 bedrooms, living room, dining area, 2 bathrooms roof patio |
| 36 | 1 | 5 | 3 bedrooms, living room, dining area, 2 bathrooms, roof patio |
| 37 | 1 | 2 | 1 bedroom, living room, roof patio |
| 38 | 1 | 2 | 1 bedroom, living room, roof patio |
| TOTAL | 64 |
Regular flats
Since each flat has the corridor at its back and all its windows in one wall only (except the end flats), the living area and bedroom are always at the front with windows; kitchens bathrooms and WCs are always at the back without. There are a number of different Types of flat in Mountjoy House, but really the differences between many of them are small. The most standard layout (Type 26 and Type 27 on floors 1 and 3; Type 31 and Type 32 on floors 2, 4 and 5) has a bedroom at the front with a bathroom and a WC behind it; and a living area next to it, with a kitchen taking a chunk out of it at the rear, leaving an L shaped living room. At each end of the block the flats are smaller or differently shaped because of the stairs and lifts (Type 28 and Type 29). Some of the corner flats have two bedrooms because of the extra window space (Type 25 and Type 30).
Penthouse Flats
There are duplex (2 floor) penthouses on floors 6 and 7. The lower level has a bedroom, bathroom, WC, kitchen and living area. But the unusual attraction is the living area in the centre which is double height, and surrounded upstairs by a gallery off which there are two bedrooms and a bathroom. (Type 35 and Type 36). (At the ends of the block, they are one on floor only and smaller, but somewhat larger than their cousins in Gilbert House). (Types 33, 34, 37 and 38)).