Extension or loft conversion

[Iammetoday]

Extension or loft conversion. We need more space and not sure what to do. Extension 2 floors or loft conversion but then we would lose the smallest box room to stairs?

We put a dormer on the side we could put the stairs over the stairs and keep the 3rd bedroom well we converted it to an en-suite cost is around £50k including reroofing. A two story extension at the time was more than double.

Thanks @somewhereovertherain

I would do 2 storey extension. It will probably be 80k+ now but worth it if you need more space.

2 storey extension will be much more expensive and take longer. Depends how much space you need/ budget. If budget ok, I would do the 2 storey ext!

I'd speak to an architect, see what is possible and get some drawings done. You can then get some quotes? A two storey extension would be my preference, but it really depends on layout and what you can do that meets building/planning regs.

I did both and I would say the loft is more valuable to me than the ground floor. The loft also added 2 bedrooms and a bathroom, the ground floor just added about 11SQM of space, so from a SQF addition to the house the loft seems to be much more valuable?

A two storey extension would probably cost at least twice as much wouldn't it? Have you been in touch with any local builders to get an idea of costs and what's doable? A dormer conversion might mean you don't need to lose the box room.
It also depends on what kind of space you need? More living space or just bedroom?

OP mentions a double storey extension.

Obviously the extension is going to add most value, but that will be reflected in the cost of the works! If I could get a double storey extension for 80k as mentioned upthread, I'd bite their hand off! Unfortunately you'll probably need to double that at least.

If money isn't an issue, the extension is a no brainer, as it will give you space on both levels and avoid your home possibly becoming top heavy. With resale in mind, a lot of buyers prefer bedrooms on 1 level too.

We thought about this, the cheaper option for us (based on the infrastructure) was a loft conversion. However, costs were still high but was half the price of an extension based on an 1800s semi-detached.

Looked at a Shell conversion but rejected the idea, but found these guys had a decent cost calculator for a shell loft conversion.

Went for a Mansard loft and used a local contractor, slightly more expensive but was by far the most detailed quote and had the reviews to back it.

However, it honestly depends what you are looking to add. Space downstairs or knocking through for a kitchen through to living rooms are so good, and extending the back (would've loved one) but the cost was too much.

Not sure which would be best for what you want, whether you want living space or bedroom space. However, a poster above mentioned a loft is important to them, I guess for storage. We've got dormer on the back which gives us a reasonable sized double and single bedroom. We've got a velux on the front which gives us a bathroom, with crawl space along half of front and a walk in storage section, to be honest we don't need half of what we've got stored.

We were in exactly the same position.

trying to weigh up whether to go for a loft conversion or a double storey extension. Both have pros and cons, and it really depends on what kind of space you need.

A loft conversion is usually cheaper and quicker, but you’re right, you often have to sacrifice the box room for a staircase (we did!). On the flip side, it’s great for adding a bedroom and en-suite without losing garden space.

A double storey extension gives you more flexibility – you can create an open-plan kitchen/living space downstairs and an extra bedroom or bathroom upstairs. However, it’s a more extensive job and typically costs more..

We ended up doing loads of research before deciding. This guide helped us weigh up the costs and layout options for both routes if it helps:

www.loftcompare.co.uk/double-storey-extension-cost