One storey or two storey extension

[lockdownbreakdown]

I am looking for some advice on extensions

We have benefited greatly from the sudden rise in house prices in our semi rural area and can now release some equity for an extension. We love our location and dont really want to move yet. There are only three of us DH, me and DC3. We have a bog standard 3 bed semi with a good sized sitting room and kitchen diner. I want to extend the house to get an additional sitting room and utility in the side return but DH wants to spend an additional 30k to do a 2 storey extension to create a large ensuite bedroom upstairs too.

Our options

1. Single storey. We get a large extra sitting room with velux windows and lots of light with a woodburner and a good sized utility. Much less distruption and mess and all over in 12 weeks. No need to move out and the cat and stay at home. Cost about 40k.

1. Double storey. Extra bedroom with ensuite but need to move the current bathroom to achieve this. Lose the light in downstairs kitchen diner due to no velux windows. Need to move out and find someone to foster the cat for three months. However, house will then have more value as will be a four bed even though we dont really need a four bed house right now as not having any more children. Will cost an additional 30k minimum.

Thoughts?

Is there a third option of single storey extension + a loft conversion (possibly at a later date, and less likely you'll need to move out)?

Thinking of costs, it's more expensive to build a ground floor extension than for the first floor. Obviously in this case you'd have extra costs for moving the bathroom upstairs.

Would you definitely have to move out? If arranged carefully by the builder there could just be a week or two without the bathroom working and the rest would be habitable.

By building upstairs do you mean you'd impinge on the current kitchen/diner velux? Do you have a plan you could upload?

Do you just have the one loo and bath/shower?

We lived with a temporary kitchen in the dining room and just one loo and shower for 8 months. It is doable (though we did lose the plot a few times and get an Airbnb just to have a bath and central heating)!

We went for a single storey extension BUT we had foundations dug that would cope with 2 storeys at a later date.

So we cant go into the loft as the roof is too low but we can get the foundations dug to accommodate a second floor at a later date. We currently have two loos which seems plenty as there are only 3 of us. I'm just really put off the idea of a second storey as we would need to move ourselves and the cat out. It's such an upheaval!

Sorry, bathroom is already upstairs but we would need to reconfigure upstairs if we extend and then it would need to be moved.

So we would need to move out as cant live without a shower and the building would be dangerous for the cat

Yes , with a second storey we couldn't have a velux in the new sitting room . New sitting room would flow from the kitchen dinner as it would be in the side return so it would mean that both rooms would be quite dark.

Double storey. We just did a single but I’m hindsight it would have been better to do a double as once the work is underway it’s easier/more cost effective to get it all done. Although we wish we had done it we can’t be bothered to go through it all again so will stick with what we have.

If you can easily afford both, I would do it. It's always good to have extra space and will add value to your house.
Why would you need to move out? Most people stay whilst work is being done. Paying for somewhere to stay would add a lot of cost and inconvenience. As you have a second loo, you can manage without a bathroom for a short time.

What is the size of the single and double extension?

Can you not have the new bathroom done before the old one is taken out?
We had a double storey extension, going from 3 to 4 bedroom with the family bathroom becoming our ensuite and a new bathroom being built. We lived in the whole time with young children and our cat.
It is disruptive, but saves a huge amount in the long run. Plus your timings are likely a best case scenario. Ours was originally estimated at 6 months, but ended up taking a year and a half.

A year and a half!! Yes, that's the nightmare I want to avoid! My neighbours got their single storey done in 12 weeks! The single storey would be 30ft by 11 ft. Small utility and narrow sitting room. We would need to move the bathroom into the extension so couldnt do it first.

We did a double without moving out. To be honest the upstairs was the easy bit. The main problem was losing the kitchen downstairs. The extension has taken 10 months and we are almost done. We were without a kitchen for 4 months. Interestingly our builder also originally said it would take 12 weeks! Covid, supply issues and issues with the builders subcontractors has slowed everything considerably.

You still have to pay for a roof and footings, tbh the 2nd floor isn't that much of extra effort; if you do it later then you'll have two lots of inconvenience and pay for the roof twice. There is no best time to do these works!