Advice Wanted - single story extension

[Jamoe]

Afternoon All

Knowing we have a diverse crowd here there might be some useful advice.

We are looking to build a single story extension on our house to free up the study so it can be used as a bedroom (more on that later).

Our house is an L shape with garage on the side (effectively making a U shape). The idea is to fill in the gap and use the space as a study (really it's a man cave but to convince the wife I'm calling it a study). The area is pretty useless due to it being north facing and gets no sun. We were going to slab over it anyway.

[ATTACH=CONFIG]3522[/ATTACH]

https://drive.google.com/file/d/1r9EhLltB_5anhh4BxLEUDhtr-stmrg78Mw/view?usp=sharing

I have a basic estimate for £13k excl. VAT.

• Basic flat roof
• uPVC door/window
• electrics (downlights and 2 double sockets)
• additional extractor fan for small toilet and extending existing fan for Utility room
• Moving the boiler into the garage.

Additionally another £2k for a lantern light in the roof.


My searches online haven't come up with much when you only need 1 wide/roof doing so I don't have much to go on in regards to cost.

Does that seem a reasonable starting estimate? The builders themselves are known to be more expensive. They are well known, family run, been around for 60 years, good quality and very tidy finishers.


Any advice is welcome but ultimately looking for some reassurance that I'm not getting a ridiculous price.

Thanks in advance.

Jamoe

[Penfold]

Got any drawings?
Does moving the boiler to the garage give you much? It's relatively expensive. Is it because it's vented to your new space or do you want the added interior space?
How big a lantern do you want? I'll check with one of my clients which makes them for comparison.
Are you keeping the side door to the garage?
Another option is to use the existing interior kitchen door to the outside of the study and replace with a much cheaper interior door?

Normally one would work it on on the cost per sq ft or per sq metre. What is the area you're looking to infill?
As with builders I'd go with the better one if they've got a good rep or been recommended.

[Jamoe]

Got any drawings?
Normally one would work it on on the cost per sq ft or per sq metre. What is the area you're looking to infill?
Does moving the boiler to the garage give you much? It's relatively expensive. It's as it's vented to your new space or do you want the added interior space?

Roughly a midge over 9sqr meters - (2.62m x 3.44m) Looking to build a wall across that gap level with the back wall of the garage.

No drawings yet but will need to get some drawn up for building regs.

Yeap, it's vented into the new space. The boiler exhaust would need extending through the roof or roof space to the new wall. You can see if on the left side of the door.
 - Builder/Gas Engineer wasn't keen on putting it through the roof, I was happy with that, seems something extra to go wrong.
 - Extending it horizontally means having access points in the ceiling for each joint in the pipe. (technical terms fail me so please excuse)
 - Moving it does open space in the utility, I also like the fact it's not underneath a bedroom.

 I could ask for more cost breakdown regarding moving the boiler.


Edits Galore

Lantern is just a nicety to try and let in more light. It's not a huge space so it wouldn't need to be big. Really it's secondary, once I'm happy with the base price I'll work up form that and see if I can add things like bi-fold doors etc.

Will be keeping the side door to garage, it needs to be a fire door though. New builds are terrible for space and we ended up putting the tumble dryer and another freezer in the garage. Moving the boiler gives us options to have a taller freezer in the utility (only just thought of that).

Thanks for the questions Pen, already making me consider things differently

[Blunt]

Regarding the roof-light, I got a domelight from http://www.nationaldomelightcompany.co.uk/

It's triple glazed and opens (not that it ever gets hot enough)

1 No. Stardome triple skin clear UV protectedpolycarbonate dome complete with 237mm high whitesplayed MK2 PVC kerb complete with manual hingedventilation including portable winding rod. Rooflight tosuit a roof opening size of 1700mm x 940mm

Total cost 5 years ago £ 1424.40

[ATTACH=CONFIG]3523[/ATTACH][ATTACH=CONFIG]3524[/ATTACH]

[Jamoe]

Looks great Blunt, will show Helen later

[Penfold]

IF you look at about £1,200 per square metre that's a rough benchmark but obviously varies depending on the specification of the finish. So your 9 sqm would estimate to about £11,250. Factor in the cost of moving the boiler and getting it recommissioned as well as your other bits and it's not a million miles off.

UPVC Doors and windows are cheap as it's a hugely competitive market. Just grab the measurements and any ex-stock supplier will give you a guide price off their website. The lantern price is about right I guess for a 2m x 1.5m alu.  

How new is the new-build? Just make sure there's no covenant saying you need permission from the original developer. Normally it's only if it's new new but do check. Planning should be simples as it's allowed under 'permitted development'. Finally, are you ever going to consider making it two storey to increase the upstairs footprint. If that's going to be a possibility then it'd be a lot cheaper to make sure the roof is structurally sorted at this stage rather than trying to retrospectively do it a few years down the line. (Not sure how feasible that is though as it's hard to see from the photo).

[Jamoe]

Cheers Pen tanks for the advice.

The builder also mentioned checking for clauses, we bought in 2006, so 10 years old. I'm sure there isn't any active clauses, others have built already but I will do my due diligence

I don't think the price is that far of the mark, I will get some more quotes but mainly because they might suggest a solution that works better for us.

We had considered 2 stories but if we did that I wouldn't want a flat roof and because of the current shape of the roof I feel it would be a "whole new level" of pun.

[Twyst]

Have you considered moving the boiler into the loft? That way you can easily vent through the roof. Modern boilers can live quite happily in a well insulated loft I'm told.
Or, if your current boiler is not condesing, you also have the option of putting a condensing boiler in place of the hot water tank if there is better ventage from there.

[Jamoe]

We have a condensing boiler.. bane of my life as the Gas Engineers I've found don't seems to know much about them :/ that and the company that made them kinda went bust and split up and all sorts of mess.

I think moving the boiler to the loft is a bigger job but I shall enquire next time I speak with them.

Current status is really gathering more quotes which I've been slack on

[Jamoe]

So time for a bit of closure, after getting the drawings I remembered the house is sat on a concrete raft on piled foundations. After a bit of investigation we realised that this was going to get expensive for the little space we were adding.

Long story short, we moved house last week and are now settling into a new place (2 minutes from the old place). I get internet connected next week. Although it's cost a small fortune this is the forever home, the kids all get decent sized rooms, I get an office and the wife gets to write up a whole new list of jobs for me...

[BrotherTobious]

Congrats on the move mate so pleased for you!!!!

[smilodon]

Congratulations.

Just hang in there for the Internet, I know it must be hell.

[suicidal_monkey]

nice :thumbup:


...we're still looking at our expensive single story half-extension-thing

[Jamoe]

I have internet tbh enjoyed not having it, kids realised they had toys....