Extension post #11 – how much did it cost?

Whilst talking about money doesn’t come naturally to us British folk, it seems daft to write loads of posts about our extension without covering the reality of how much it all cost. Before we decided to have work done, I found very little helpful content online about the cost of extensions other than “between £1,000 and £3,000 per square metre” which is useless. So if y’all are thinking of having similar work done, or are simply nosey (as I would be), read on for a breakdown of how much our extension cost.

Pre-building work

There were a few costs before the builders arrived. These included architect fees (£775), planning application (£84) and structural engineer calculations (£714) which meant we’d spent £1,573 before anything actually changed. We could have saved money by not using an architect and just going with the builder’s interpretation of what we wanted, but we felt this was too risky.

Building work

If you’ve been following my extension posts, you’ll have a good idea of what the work included. As well as a 3 x 6 metre single pitch roof extension, we had a loo put in under the stairs and our side door moved to allow access straight into the new utility. You can see more details in the post I wrote about our plans.

Our builder project managed the work and we agreed a fixed price contract before the build began. This contract included doing all the work except for supplying/fitting the kitchen, laying the flooring and decorating. So electrics, plumbing and plastering, steels etc. were all included in the price.

The total cost of the planned building work was £37,700. I’ve written a bit more about the quotes we had in this post about choosing our architect and builder.

Any deviations from the contract meant we’d either have to pay more/less than the figure we’d agreed. As you might expect, we added more bits than we removed. This included adding another Velux, lighting above/below kitchen units, upgrading to column radiators and quite a few extra electric and plumbing bits. The extra Velux cost £365, extra electrics £775, and extra plumbing £540. We knew that we’d inevitably want to add a few bits here and there so thankfully had 10% extra planned into the budget.

So, all-in-all, all the building work plus extra bits came to £39,380. We were very lucky to have no unexpected costs during the build – I reckon that’s very rare!

Kitchen & utility

This was our next biggest cost. The kitchen & utility units came to £4,247 which for 20 units plus all the trim is crazy good. That’s because we ordered from DIY Kitchens who are significantly cheaper than elsewhere. I sounds like I’m being paid to write this but I am not (although if anyone from DIY Kitchens is reading this, gizza bell). This post is about how we planned and ordered our units.

We ordered our laminate worktops and upstands separately – these came to £617. I didn’t trust myself to fit the worktops so we paid a chap £145 to do these.

On top of that, knobs and cups for the units cost £138 which seems a ridiculous amount to spend on this but trust me, it adds up.

The sink cost £160 and tap came in at an offensively cheap £28 (let’s see how long it lasts…)

We’ve bought the tiles for our kitchen splashback but I ain’t put them up yet. These cost £125.

Then there were various other, smaller costs including pendants & bulbs for the island as well as all the other fixings I bought to use whilst fitting the kitchen/utility which came to £230 in total.

SO, absolutely all of these bits came to £5,690 which I think is quite good for a decent-sized kitchen and utility. Fitting the units ourselves probably saved us between £2,000 and £3,000, although we did have a quote of almost £4K.


When it came to choosing our appliances, it was a bit overwhelming to begin with. We soon decided to just buy whatever Which? recommended, providing it was sensibly priced. Appliances came to £2,504 in total, broken down as follows:

  • Stoves range & extractor hood – £988
  • Hisense integrated fridge freezer – £307
  • Bosch washing machine – £400
  • Bosch tumble dryer – £500
  • Integrated Hisense dishwasher – £309


We’ve had Karndean LVT flooring fitted to the extension, dining area and utility. This came to around 35sq. metres and cost £2,045, including fitting. This felt like a lot to pay for flooring but it should last a lot longer than any other alternative and so will hopefully be worth it in the long run.


The building contract didn’t include the loo vanity unit & tap or supply/fitting of tiles. These costs came to £368.


Haz saved us a load of cash by doing all the decorating (she has now painted every square inch of the house). So we only had to pay for paint, paintbrushes etc. which came to £164. I think it would have been £1,000+ if we’d used a decorator.


Who doesn’t love a sundry category? The place where you put stuff that you didn’t budget for. This included pendant cables for the island lights, door knobs & dipping the doors we bought from FB marketplace. Cost = £92.

The numbers are in…

In case you’re not phenomenally good at mental arithmetic, the total cost of the extension + other bits came to £51,274 (give or take a couple of quid). The original budget we set was £55K, including a small contingency, so we’re glad to have come in under that figure.

Whilst it feels good to imagine that we’ve added more value than that to the house, it shouldn’t matter too much as we plan on living here for a looong time.

It’s worth mentioning that these figures don’t include furniture, the patio that I laid outside the extension, or any of various bits we’ve bought to make the new space look pretty. As you might expect, these add up, so I’d definitely recommend budgeting for this stuff.

It feels a little odd being so transparent about what we spent on the extension but I hope that it’ll prove really useful to some of you guys when budgeting for your own work. We’re based in Yorkshire so probably worth lobbing an extra chunk of cash to your budget if you’re in London/South East.

I’ve said it before but DEFINITELY get multiple quotes for the work. We got 5 quotes and they varied by £17K… So unless you’ve got a spare 17 grand knocking around, it’s worth getting in touch with a few builders.


Fitting our ‘DIY Kitchens’ kitchen

As a true Yorkshireman, I love a bargain. So saving money by fitting the kitchen myself was very appealing. When we had our first fitting quote back of almost £4K that sealed the deal. I could buy a load of awesome new tools, fit the kitchen myself and still be a few grand better off?! Sure, a bit of DIY/woodwork experience helps, but it’s largely a case of getting stuff level and fixing it in place. This is a relatively short summary of how it went. I may, one day, get round to doing a a few in depth posts on the process.

In case you’re interested in how we went about planning & ordering our DIY Kitchens kitchen & utility, have a peek at this post.

Setting out

Like so many DIY jobs, spending some time looking at what you’re working with is key. This involved measuring up, checking variations in floor level, irregularities in walls, different wall types that would need to be fixed to etc.

We were pretty lucky in that the plasterers did an awesome job of getting the walls level and plumb. For the most part, the floor was level, but there were some dodgy areas. Nothing that the adjustable unit feet couldn’t sort out.

I used a laser level to mark the top position of all floor units on the walls.

This baby is definitely a must for a job like this and only cost £30. I got an irrational amount of satisfaction from seeing the laser light up dust on top of the units.

The last thing to do before fixing units in place was to make any adjustments. The back of the sink unit needed cutting out.

I also needed to make some pretty major changes to the units that sat against the kitchen pillar. The wall units took bloody ages and almost led to a nervous breakdown.

Onto the next stage.

Fixing the units in place

With all the levels set and units adjusted, it was onto fixing the units in place. I started with the wall units so that the the base units weren’t in the way. The laser level worked a treat, but having a 6ft spirit level was also really helpful.

I used Corefix dot & dab fixings for the wall units. They’re pricey for what they are but having confidence that our wall units won’t fall down in the middle of the night is priceless.

With the wall units in place, I lined the base units up with them to keep things symmetrical.

The corner where base units met was a bit tricky to get right but after cutting a corner post to size it looked smart.

I used L brackets and wall plugs to fix the base units and tall units against the wall.

The kitchen came with wee screws to tighten the units against each other.

Before whapping the doors back on, I fixed all the cups and knobs in place. I spent ages on this ‘cos one wrongly drilled hole would lead to a great deal of sadness.


With the units fixed in place, I moved onto adding trim, starting with the pelmets that sit on the underside of the wall units.

Having brand new, high tooth count blades for cutting these bits is key to get sharp cuts and avoid tear out.

For the pelmet/cornice I used mitre adhesive to join the sections before screwing onto the units with fixit blocks/screws.

Once the floor was laid, I added the plinths. These babies just clip onto the unit legs.

Where there were gaps between units and the wall, I added filler panels. If I was a proper person I would have scribed these and used a jigsaw to cut them out. But, the walls were very close to plumb and my £25 jigsaw wasn’t up to the task. A circular saw ended up doing a good job.

For the end panels, I either cut them down using my table saw or circular saw, depending on the end panel size. I then screwed them in place from the inside of the unit.


We hired a man to do most of the worktop work because I wasn’t confident doing the 90 degree join where the laminate changes direction. I did cut the island and utility worktops, which involved roughly cutting them to size with a jigsaw and then using a 1/2 inch router against a spirit level to give a clean cut.

After cutting the upstands to length, I fixed them to the wall with some adhesive and added some clear sealant at the bottom.

This was the first time I’ve ever done anything like this so it was pretty stressful and slow going. However, it’s not that complicated a process and I’d actually really like to do another! The key to doing a good job is definitely in the planning and taking time to set out properly.


Extension post # 10 – finito!

Four and a half months later and we’re pretty much there. It feels sooooo good. We’ve still got a few things to buy/do before it’s 100% finished but, for now, we’re just enjoying it!

Pre-extension, the kitchen was our least favourite room in the house, by far. It was tiny, the units were falling apart, and only 1 of the gas hobs worked. We now have the kitchen of our dreams and feel incredibly lucky!

Being the intensely sad people that we are, we’ve been speaking about having a range cooker and kitchen island for a few years. Cooking is now a joyful experience and so we fight over who gets to be chef. We eat sat at the island most nights which is so, so much nicer than being slumped on the living room sofa like we used to be.

One of the jobs still do to is tiling the kitchen wall. We’re going to use these tiles in a herringbone pattern – wish me luck, I’ll need it.

We went for Karndean LVT flooring which was pricey but looks great and is easy to clean. Apparently it lasts forever but this furry fella may have other ideas.

Opposite the kitchen we’ve got a wee seating area. One day I’ll make a coffee table to go here but for now it works well just as a place to flop. Basil loves to chill here whilst barking at cats in the garden and watching his mother cook.

The door at the back of the kitchen leads to a small utility room.

Initially, I wasn’t fussed about having a utility, but I’m glad that Haz pushed for it because it’s so handy to have this space separate from the kitchen. Plus, it’s a great place to leave a muddy dog to dry off.

As part of the work, a loo was sneaked in under the stairs. Whilst cat swinging isn’t an option in here, not having to go upstairs for a wazz is a well nice.

From outside, the extension looks really cosy. I’ll finish the patio in spring once the earth sat in the pond that used to be on the left hand side has had chance to settle over winter. I should probably give the patio a good clean…

We’re so chuffed with how the extension has transformed our home. Although, having said that, I’m hoping that it’ll be many years until we have any more building work done 🙂

Once we’ve finished everything, I’ll do a post on where we got stuff from. I may also do a post about how much everything cost as I’m sure that’ll be helpful for people planning on having similar work done.


Planning & ordering our ‘DIY Kitchens’ kitchen

We spent a ridiculous number of hours researching manufacturers and then designing our kitchen. Overall, I found it pretty fun but there’s a bewildering number of decisions to be made. This post’s all about why we chose our kitchen manufacturer and how we planned out the design. It should be helpful if you’re getting a new kitchen soon, particularly if you buy from DIY Kitchens.

Choosing a kitchen manufacturer

After much deliberation, we decided to order from DIY Kitchens because they came highly recommended and are far cheaper than other kitchen suppliers. The main reason they’re more affordable than competitors is that, as the name suggests, the onus is on you as the customer to plan and order your own kitchen so whilst the staff at DIY Kitchens are really helpful, it’s ultimately down to you when it comes to the design and ordering units. This might immediately put some people off and that’s fair enough – we were willing to put the time in to save a few bob without having to compromise on quality.

We ordered a total of 20 kitchen + utility units and it came to £4,300 (not including any appliances, worktop, sink etc.) If you’ve not ordered a kitchen before this may sound a lot, but it was 30-50% cheaper than the quotes we had from Wren and a local independent firm. Initially, I thought DIY Kitchens’ lower prices would mean lower quality but we’re well pleased with how robustly everything is built.

Another factor that led to us choosing DIY Kitchens was the huge variety of units on offer. Initially, this was a tad daunting but we soon felt fairly confident and it meant that we could design our kitchen exactly how we wanted to. We found that during appointments with other suppliers there was a lot of “oh no we don’t do those in that size” sort of responses to our questions which was frustrating, especially when you’re shelling out so much dosh. DIY Kitchens has a far wider range of units so if they don’t have what you want it’s probably time to get your toolbox out and make the kitchen yourself!

One aspect of buying from DIY Kitchens that will put some people off is that they don’t offer a fitting service. This wasn’t a problem for us as I fitted our kitchen, but the convenience of having fitting rolled into your kitchen purchase will be a big plus for some. If I were to pay for fitting, I would personally use a local fitter anyway. A lot of kitchen manufacturers make a big chunk of their margin from fitting (Wren quoted us £3.5K to fit their kitchen!!!) whilst local outfits are typically much more reasonable.

Getting inspired

I would definitely recommend visiting a few kitchen showrooms before doing anything else. We found it really helpful for inspiration and took approx. 392 photos at each showroom. If you’re considering ordering from DIY Kitchens, a visit to their showroom is a must, although there’s only one and it’s in Pontefract so not ideal if you’re hours away but potentially still worth it to save a few grand. As well as inspiration, visiting DIY Kitchens helped us choose the style and colour. There are loads of different styles from modern handleless designs to more traditional, shaker-style options. We’ve gone somewhere in the middle – Clayton shaker in Dove Grey for the L-shaped units of the kitchen with an island in Carbon.

Another great place for inspiration is Pinterest. It’s pretty much exclusively aspirational stuff that only the rich can afford but regardless, it’s great for giving you ideas on kitchen layout, colours, unit types etc.

Design appointments

With a decent idea of what we were after, we found it really helpful to have a couple of design meetings with kitchen manufacturers. Even though we didn’t end up using them, the advice and ideas they provided were invaluable. It meant that when it came to designing with DIY Kitchens we knew pretty much exactly what we were after. Granted, spending a couple of hours with a kitchen designer and then not using them must be frustrating for those businesses, but the way I see it they’ve not given me a strong enough reason to buy from them and that’s not my fault!

DIY Kitchens’ product range

If, like me, you’ve never bought a kitchen before, you will probably be baffled by the breadth of units that you can buy. DIY Kitchens has a particularly wide product range which at first can be a tad daunting but it’s ultimately a good thing as it means you’re unlikely to have to compromise on anything.

To make the most of the variety of units available, I spent aaaages plodding through every product on their website so that when it came to deciding on a final design, we’d have the best combination of units to suit our needs. Whilst this wasn’t overly fun, it was very worthwhile and I’d really recommend doing this if you end up ordering from these guys.

This is probably a good time to familiarise yourself with all the kitchen lingo too. For example, I had absolutely no idea what plinths, pelmets, cornices, drawerline units, fillers, end panels etc. were before I started the process but the advice guides were great for getting clued up on this stuff.


The space

Before getting too excited and throwing wine racks all over the place, measuring the space VERY accurately before you start planning is key. You’re far better off ordering units that add up to 5cm or so less wide than the space than them being 1cm wider as you can use fillers to neatly hide any gaps whereas you can’t make the units any narrower. When you do come to planning out your units, remember to factor in the width of end panels (the panels the tidy up the end of a kitchen run) and fillers (that, for example, you might use either side of a range cooker or non-integrated dishwasher). They’re only around 18mm each, but they add up.

Providing your kitchen ceilings aren’t stupidly low, unit height shouldn’t be an issue. If you choose any tall units (like integrated fridge freezer or larder unit), the standard height unit is 212cm in total (197cm unit + 15cm feet) which should line up with the top of any wall units you go for. There are some taller units available, but tbh you’d have to either be 7ft tall or use a stepladder to get to the top of these. Here’s a diagram I did which helped me understand the height of tall units and how base + wall units line up with them based on a 40mm deep worktop.

Anything irregular also needs to be factored in. For example, there’s a 66cm wide pillar that protrudes 13cm from the wall half way down the main wall of our kitchen. Whilst we have units up against the pillar, they’re just basic units with shelves because anything fancier (eg: drawers, fancy mechanisms) wouldn’t work because I had to cut out the back of the units when fitting – you can’t cut out anything with a mechanism. It’s worth noting that altering the units to fit round something like our pillar is a faff and took me hours so chances are fitters would hate this.

The pillar

As well as considering irregularities like pillars, taking into account how your kitchen will flow is vital. A quick Google search and you’ll come across loads of articles about ‘the triangle’ which advises that the sink, fridge, and cooker should be positioned in a triangle so they can easily be moved between. We’ve gone a bit maverick and avoided positioning these three elements in a triangle because we didn’t want the sink or hob on the island, but I do think it’d be a good thing to stick to if it suits your kitchen space.

In terms of spacing, the ideal width of kitchen walkways is between 90 and 100cm. It’s possible to go slightly smaller but it’ll start getting tricky for 2 people to pass each other and you may not be able to, for example, walk past the dishwasher when it’s open. Some people go bigger than one metre but there surely comes a point where it’s actually a bit inconvenient to have to get from one side of your kitchen to the other. We’ve gone for a 1 metre gap all around our kitchen units which is just about right IMO.

Planning tool

By this point you should be fairly well-equipped to get cracking with planning. As I mentioned, with DIY Kitchens the onus is on you to get the planning right so it’s worth spending a decent chunk of time on otherwise you could make costly mistakes. The customer services people are really helpful with answering even very specific questions and I made the most of that!

The best starting point for planning is DIY Kitchens’ planning tool. This allows you to create a virtual space to the exact dimensions of your kitchen. There’s a bird’s eye view function that can be used for selecting and positioning units and then a 3D virtual view that allows you to move around the space to get a better idea of how things look and the flow of the space. It’s pretty much just Sims with the main difference being that this is a productive use of time.

There’s a lot of trial and error but that’s fine as you can easily swap in and swap out different units until you arrive at a combination that you’re happy with. Something that worked well for us was to write down all the bits we had in our kitchen and then plan where we’d put these in our new kitchen, considering any other bits we may need in the future.

When using the planning tool, there are a few options including whether you want soft close drawer runners and what side you want the hinge. Soft close is a no brainer IMO. As for hinge side, we positioned them so that all units would open for access from the range cooker which is in the middle of the kitchen run. So basically, you’re never having to walk around an open door to have to grab stuff.

More planning…

It’d probably be absolutely fine to finalise your kitchen design on the planning tool and then order based on that list of units. I was keen to do a double check of everything and found that planning out all the units on a spreadsheet worked well.

One of the main benefits of planning out on a spreadsheet is that it gives you 100% flexibility. The planning tool is really good, but it can sometimes make assumptions that aren’t right. For example, when we added our island to the planning tool, the end panels weren’t selected in the right place so by using the spready I was able to adjust that.

After planning out our kitchen, I put together an order list with details like dimensions, hinge side, colour etc. to make sure that when it came to actually ordering I felt confident about not making mistakes. This may seem a little OTT, but I’d rather spend another couple of hours prepping than get the order wrong.

DIY Kitchens don’t leave the risk of ordering the wrong stuff exclusively with you. They’ll contact you after you’ve ordered if there’s anything in your order that they think doesn’t look right which is a handy safety net.

Cutting costs

Whilst DIY Kitchens came out a lot cheaper than competitors, it’s still a big purchase and some savvy planning can easily save a few hundred quid, maybe even over a grand.

The first tip is that, as a general rule, anything with a mechanism is more expensive. We saved some money by getting as few drawers a we need and trying to avoid the expensive, but very tempting fancier bits of kit. Having said that, we couldn’t say no to the Le Mans 2 corner unit which is pretty damn sexy.

If you have a couple of wall units next to each other, it’ll likely save you a few quid to get one large unit with double doors than two separate units. We’ve got a 90cm wide double wall unit in the utility which was a lot cheap than getting two single units that added up to 90cm.

After deciding on your units, you can choose the trim that will finish it off. The plinth is the section that sits at the bottom of the units to hide legs, the pelmet is the section that you attach to the underside of wall units and cornice is the stuff that sits on top of wall and tall units. Whilst plinth is a must, you don’t actually have to buy pelmet or cornice. In our opinion, kitchens without these look a bit unfinished but that’s purely personal preference and by leaving these out we’d have saved a decent amount.

Another cost-cutting option is to buy these elements of trim (fillers and end panels included) in carcase material rather than door material. This basically means that they’re made of the material used to build the units rather than the doors. It’s therefore slightly different wood and is colour-matched to the door material rather than being an exact match. For some kitchen ranges and colours, such as our Dove Grey Clayton units, the carcase bits of trim are a very close colour match whereas the Carbon colour of our island units is clearly a different colour to the equivalent carcase material. Like all of these decisions, it’s totally subjective, but if you’re on a tight budget this is another way of reducing your outlay.

Whilst you definitely need end panels to finish off, for example, the side of an integrated dishwasher, there are scenarios where you don’t necessarily need to shell out. Our extractor hood has wall units to either side of it which we could have bought end panels for. However, because the carcase material is a really good match for the door material of a Dove Grey Clayton kitchen, we’ve not actually bothered with end panels and it looks great.

A final tip for y’all: buying non-integrated appliances will save you money. Firstly, the appliance itself will likely be cheaper than an integrated equivalent (and, in the case of fridge freezers, will be more spacious), but it’ll also mean you don’t have to buy any units the house the appliance. We’ve gone for integrated appliances in the kitchen because we don’t like the look of non-integrated, but it’s cost us a few hundred quid more. However, don’t assume all integrated appliances will cost more – our integrated dishwasher was pretty cheap and only required us to add a DIY Kitchens door to the front of it.

I hope y’all found this post helpful. You may be interested in having a peek at other posts like how I fitted our kitchen, what we got up to in 2020 or how much our extension cost.