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myDownstairs Toilet Installation Cost
At a Glance
- The average cost to fit a downstairs toilet is around £3,000
- The job will take approximately 7 – 10 days to complete
- Downstairs toilet installation costs in 2026 by type, specification, and location.
- What's involved in the job and how long it takes.
- How to find a local bathroom specialist using MyJobQuote.
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Want to know how much it will cost you to build a downstairs toilet?
In this comprehensive cost guide, we look at the typical prices for different types of downstairs toilet installations. From the understairs toilets to the small cloakroom toilets. We'll also cover labour fees, material costs and other key factors that may impact the overall price.
To give you a quick estimate, it will likely cost around £3,000 on average, to install a new toilet under the stairs.
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Take a look at the article below for all your downstairs toilet cost information!
£3,000
Table of Contents
- How Much to Install a Downstairs Toilet?
- Labour Costs and Timescales
- Downstairs Toilet Supply Costs
- Additional Costs
- Cost Factors of Installing Downstairs Toilet
- What's Involved in Installing Downstairs Toilet?
- Space Saving Toilet Designs
- Cost of Removing a Downstairs Toilet
- Checklist: Hiring a Bathroom Specialist to Install a Downstairs Toilet
- What Size Space Do I Need For a Toilet?
- FAQs
How Much to Install a Downstairs Toilet?
The average cost to install a downstairs toilet in the UK is £2,000 to £4,000, covering labour, sanitaryware, and finishing. Most installations include a toilet, basin, radiator or heated towel rail, and either a window or extractor fan for ventilation.
What is your main reason for a downstairs toilet installation?
Installing an additional toilet facility
2 votes - 33%33% of votes
Relocating or replacing existing toilet/bathroom
2 votes - 33%33% of votes
Making the toilet more accessible
1 votes - 17%17% of votes
Part of a wider home renovation project
1 votes - 17%17% of votes
To increase property value
0 votes - 0%0% of votes
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The biggest variable is your plumbing situation. The closer your chosen space is to existing waste and water pipes, the lower the overall cost. If there is no nearby waste pipe, a Saniflo macerator can be fitted as an alternative to running new pipework. Other factors that affect the final price include the quality of fixtures you choose, the level of finish, access to the space, and where in the UK you are based.
I have a lot of space under my stairs, which I'm currently using as storage; however, I have no downstairs toilet. How much would it cost to put a toilet under my stairs, and how long would it take?
"£1,000 to £2,000, depending on where the water & waste supply/outlet is. A Saniflo system can be used if there is no waste supply nearby. It should take 2-5 days."
Downstairs Toilet Installation Prices
The table below gives a breakdown of typical costs for the individual elements of a downstairs toilet installation. Plumbing costs in particular will vary depending on how close your chosen space is to existing drainage.
| Job | Labour Cost | Material Cost | Total Cost |
|---|---|---|---|
| Toilet and basin | £300 – £400 | £130 – £780 | £430 – £1,180 |
| Plumbing (existing drains) | £200 – £400 | £50 – £100 | £250 – £500 |
| Plumbing (new pipework) | £300 – £700 | £100 – £200 | £400 – £900 |
| Saniflo macerator | £150 – £250 | £350 – £650 | £500 – £900 |
| Stud partition walls | £250 – £525 | £90 – £100 | £345 – £625 |
| Fully tiled walls | £450 – £600 | £105 – £3,950 | £555 – £4,550 |
| Tiled floor | £300 – £600 | £135 – £345 | £435 – £945 |
| Vinyl flooring | £150 – £300 | £15 – £60 | £165 – £360 |
| Plastering | £100 – £300 | Included in the cost | £100 – £300 |
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Labour Costs and Timescales
Installing a downstairs toilet typically involves several trades working in sequence. You can reduce costs by hiring a multi-skilled bathroom fitter who can coordinate the full job and quote for the work as a whole rather than per item. A qualified bathroom fitter will usually complete the installation in 7 to 10 days.
| Installation item | Labour cost | Duration |
|---|---|---|
| Plumbing (toilet, basin, pipework) | £300 – £700 | 2 to 4 days |
| Electrical (lighting, extractor fan) | £190 – £300 | 2 to 4 hours |
| Joinery (stud walls, door, skirting) | £250 – £525 | 1 to 3 days |
| Plastering | £100 – £300 | 1 day |
| Tiling (walls and floor) | £300 – £600 | 2 to 3 days |
| Flooring | £150 – £300 | 1 to 2 days |
| Radiator or heated towel rail | £250 – £300 | 3 to 4 hours |
| Accessories | £50 – £150 | 1 to 2 hours |
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Downstairs Toilet Supply Costs
If you're sourcing your own sanitaryware, the table below shows typical costs for a standard downstairs toilet. Prices vary by specification – budget options are functional, while mid-range and premium suites offer better aesthetics and durability.
| Item | Low specification | Medium specification | High specification |
|---|---|---|---|
| Sink | £42 | £150 | £270 |
| Tap(s) | £27 | £250 | £420 |
| Toilet | £65 | £750 | £1,530 |
| Floor tiles (1.5m²) | £15 | £50 | £135 |
| Vinyl flooring (1.5m²) | £15 | £40 | £60 |
Additional Costs
Whilst the basics of your downstairs WC may be the toilet itself and a sink, there are many other items you may wish to add to complete your room.
If you have the space, adding a bath and/or shower to the room gives you an extra option if you have a big family trying to get ready in the morning.
The bath itself will cost £70 – £1,200 and a shower (the enclosure plus the shower itself) will cost between £200 and £1,400.
If you’re short on space, there is the option of installing a shower unit over a bath, or a walk-in shower bath – the latter costs between £1,500 and £2,000.
Heating
There are two basic types of heating available for use in a downstairs toilet:
- A Standard Radiator
- Underfloor Heating
A standard radiator costs on average £40 depending on size and type, although the size needed for a downstairs WC is likely to be smaller and therefore relatively cheap.
On the other hand, installing underfloor heating costs around £800. However, if the rest of your downstairs has underfloor heating, this will mean no substantial temperature changes between rooms.
One benefit of underfloor heating is that it doesn’t get dusty and then ‘bake’ the dust like radiators do, which often lends the air a stale feel.
Air Flow
A downstairs bathroom can get steamy, sweaty and smelly; three excellent reasons to have good airflow! If you have a window in the room, this is the best option as it is free to use and offers additional light. A small double-glazed window will cost approximately £150, but if you’re unable to have a window in your new downstairs toilet, an extractor fan is the next best thing.
Installing a bathroom extractor fan costs around £300 (supply and fit), but it’s worth it to save the rest of your house from potential damp patches.
Accessories
The finishing touches to your bathroom are likely the little extras that make it personalised to your needs. Things such as a towel rail, a small shelf, a cabinet, a light fitting or a shaving plug.
| Item | Lowest cost | Highest cost |
|---|---|---|
| Hand towel rail/ring | £7 | £35 |
| Bathroom shelf | £6 | £25 |
| Bathroom cabinet | £22 | £250 |
| Light fitting | £10 | £104 |
| Shaving plug | £3 | £27 |
| Extractor fan | £12 | £99 |
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It should be noted that any lights must be suitable for bathrooms due to the possibility of steam getting into the electrics.
Waste Disposal
Waste disposal is always a consideration during a downstairs toilet installation. Your builder will assess the waste generated and arrange the best means of disposal, usually a skip, costing between £60 and £100 depending on the size required.
Room Decoration
If you're not tiling your walls, or opting for partial tiling only, you will likely want to decorate the rest of the room with paint or wallpaper. A painter and decorator will often charge £150 to £200 per day, and depending on the size of the room, it could take 2 to 3 days. You will also need to factor in the cost of the paint or wallpaper.
I need a quote for installing a toilet in an understairs room. How much would this cost?
"It depends on whether there is a waste and water supply there already. This would cost about £80 for a re-install, more if it would involve plumbing in of the water supply. A good option would be a toilet with a small hand basin on top of the cistern. The waste water from the sink goes directly into the cistern, which saves water and space, as some of these areas can be very tight."
Cost Factors of Installing Downstairs Toilet
Several factors can determine your overall downstairs toilet installation costs. Here are the key things you need to consider when planning your budget:
- Your Location — The location of your property affects the overall cost. Labour costs tend to be higher in London and the South East than in other parts of the UK.
- Age of Your Property — Older properties can present challenges such as outdated plumbing, solid concrete walls, or wattle and daub, all of which can add to the costs of installing your pipework, electrics and extractor fan. There may also be limitations if fitting your downstairs toilet in a listed building.
- Unexpected Issues — Coming across unexpected issues will affect the overall cost of your project, as well as the timeline. A broken or damaged pipe, cracked brickwork, or leaking drains will result in delays and further costs.
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What's Involved in Installing Downstairs Toilet?
Installing a downstairs toilet isn't always simple. A downstairs toilet tends to include a toilet, a sink, a mirror, a radiator or heated towel rail, and a window or extractor fan and requires skills in joinery, plumbing, electrics, plastering, and tiling.
When it comes to rerouting a soil pipe or adding hot and cold water feeds, hiring a skilled downstairs toilet installer for safety reasons will be money well spent.
With MyJobQuote, you can request several quotes from local bathroom installers. It's fast, free, and there's no obligation to go ahead.
Before the Job Starts
- Survey and Planning — Your bathroom fitter will inspect the current plumbing and drainage in your house, as well as near the prospective bathroom. They will identify your boiler or hot water system, give them a good idea of how to lay the pipes around your property, and draft up a quote for the work.
- Removing Existing Fixtures — Any existing flooring and wall coverings will be removed, such as old tiling or wallpaper, along with any existing fixtures and fittings such as electrical sockets.
During the Job
- Electrical Work — If no light fitting exists in the room, your electrician will ascertain the best place and add the wiring.
- Window or Extractor Fan — If you need a new window or extractor fan, your builder will fit it at this stage, both to create the least mess at the start and to provide extra light and adequate ventilation when completing the rest of the work.
- Pipework — Hot and cold water supply pipes will be run under the floorboards to where your toilet and sink will be. If you have a cast iron soil pipe, your plumber will replace all or part of it with a plastic section to connect the new toilet waste pipe.
- Wall Preparation — Your walls will be prepared. Some walls may need insulating, then installing plasterboards, skimming with plaster and painting. A joiner will add any woodwork required, such as your door frame and skirting boards.
After the Job
- Installing Fixtures — Your plumber will install your basin and toilet and connect them to the drainage pipes, along with a small radiator or heated towel rail.
- Tiling and Finishing — A tiler will tile your walls and flooring, and any bathroom cabinets or accessories will be fitted at this stage.
Space Saving Toilet Designs
Downstairs toilets come in a lot of different styles, but if you want to take up minimal space, consider one of the following:
- Wall Hung Toilets
- Back to Wall Toilets
- Short Projection Toilets
- Corner Toilets
- Toilet Sink Combination Unit
Let's take a look in more detail.
Toilets which have their back to the wall, hang from the wall, and these take up very little space. However, there will need to be room behind that wall to place the hidden cistern. A back to wall or wall-hung toilet costs between £100 and £450.
A suitable space-saver is a close-coupled toilet – that is, one with a small cistern attached directly behind the toilet seat. Some come as ‘short projection’, meaning the distance between the front of the pan and the wall is minimal, and some are ‘fully shrouded,’ meaning there is no gap behind the toilet for the unsightly soil pipe.
A standard close-coupled toilet will cost between £45 and £350, with short projection ones costing between £160 and £270. A fully shrouded toilet will cost you £140 – £175.
You can also get a diagonal toilet, which will fit neatly into a corner – this can be a great space saver. These cost £150 – £200.
Combination Toilets
Finally, you could get one of the two kinds of combination toilets. Firstly, you can get one with a sink over the top of the cistern. This means you need only accommodate the footprint of the toilet.
You would also need to consider the surrounding space to ensure you don’t have to straddle the toilet to wash your hands! These cost between £185 and £350.
The second type is an all-in-one toilet which comprises a basin, toilet and cupboard, all in one small unit. These come in sizes as small as 90cm wide and 40cm front to back and cost £250 – £380.
Sink & Pedestal Options
If you do not want a combination sink and toilet, you’ll need a separate basin. Again, these come in different styles, suitable for varying shapes and styles of downstairs WC.
- Firstly, you have a classic pedestal basin. These don’t have any specific space-saving features, but they have a small footprint, and you can find ones with a smaller bowl. These cost between £30 and £250.
- An alternative is a cloakroom basin, which attaches to the wall. These tend to be very compact and designed to fit tight spaces. You can get narrow ones, short ones and also diagonal ones made to fit a tight corner. A cloakroom basin costs between £38 and £90.
- If you’d like some extra storage space, you could opt for a cupboard or countertop basin. These can be very narrow and fit into small spaces. You can buy the two items separately (a countertop basin and a separate cupboard), but a combined, small unit will cost between £100 and £600—a countertop basin on its own costs between £30 and £250.
Cost of Removing a Downstairs Toilet
A downstairs toilet can add value to your property, but if you wish to relocate or remove it entirely, a bathroom fitter who can handle plumbing and electrics can dismantle it within a day at a cost of £150 to £250. If you're in any doubt, call in a plumber to ensure your pipes, including your soil pipe, are sealed, and your water is redirected.
If you have hired a professional to do the job, they should have planned for waste disposal. If you are doing it yourself, a small skip will cost around £60, or you can take the waste to your local recycling centre. Be aware that some centres don't accept vans and may charge between £5 and £25 per item.
Checklist: Hiring a Bathroom Specialist to Install a Downstairs Toilet
If you’re looking to hire a professional bathroom fitter to complete this job for you, here are some things you’ll need to complete or consider:
- Are they a member of a recognised trade body? Look for membership of the Association of Plumbing and Heating Contractors (APHC), the Chartered Institute of Plumbing and Heating Engineers (CIPHE), or WaterSafe, the national accreditation scheme for approved plumbers.
- Are they TrustMark registered? Businesses registered with this government-endorsed scheme are vetted for quality workmanship, trading practices, and customer service.
- Do they have insurance? Public liability insurance protects you if something goes wrong during your downstairs toilet installation.
- Will they provide an itemised quote? Ask for a full breakdown of the downstairs toilet cost, so you know what is included and whether there are any additional costs.
- Do they have experience? Ensure they have plenty of experience with installing a downstairs toilet.
- Do they have examples of similar work? Ask to see photos of previous downstairs toilet installations, or check their MyJobQuote profile for examples of previous work.
- Do they have positive reviews? Check their MyJobQuote profile to read feedback from previous customers before committing.
What Size Space Do I Need For a Toilet?
You can put a downstairs toilet in a surprisingly small space. In fact, many opt to put a toilet under the stairs! The minimum space for a toilet you will need is 70cm wide by 130cm long, but this would function without comfort. Allowing 80cm x 140 gives you a bit more room to move.
If you are considering installing an under stairs toilet, you will need at least 2m of headroom at the toilet position, and the sloped ceiling can limit where fixtures are placed. Hidden pipework connecting to existing drains may also add to your under stairs toilet costs, and an extractor fan will typically be required for adequate ventilation.
When choosing your location, consider which way the door will open – a door that swings into a hallway or living area can affect day-to-day usability. Positioning the toilet close to existing pipework will also keep costs down, as shorter pipe runs mean less labour time for your plumber.
There is a huge range of bathroom items available for fitting into tiny spaces, so although you'll need to think small, you'll have a big choice.
FAQs
How much value does a downstairs toilet add to a property?
A downstairs toilet can add around 5% to the value of your property, provided the installation is attractive, well-located, and complies with building regulations.
Can I only install a downstairs toilet in a room that already has water access?
No – a skilled plumber can route pipes to almost any area of your home. Some locations may be more expensive or complex to connect, and your plumber will advise on the best approach before work begins.
Should I do the plumbing and electrical work on my downstairs toilet myself?
Downstairs toilet plumbing and electrical work is not a job for a novice. Electricity is hazardous and water can cause serious damage, so unless you’re confident in both skills, you’re better off using a qualified professional.
How do I plan my downstairs bathroom?
Planning a downstairs toilet installation involves more details than most people expect, such as which way the door opens, how much clearance you need in front of the toilet, and the best layout for the space. If you’re unsure, a bathroom specialist can help you refine your plans, often free of charge. Always go through your final plans with your contractor before work starts.
Do I need planning permission for a downstairs toilet?
Planning permission is rarely needed for a downstairs toilet installation, as it falls within the original footprint of the house under Permitted Development Rights. You will only need planning permission if the toilet forms part of an extension, or if you live in a conservation area or a listed building. If in doubt, contact your local planning authority – you can apply online for around £200.
Do I need building regulations approval for a downstairs toilet?
Yes. Installing a downstairs toilet requires building regulations approval, and your installer should provide a building control completion certificate on sign-off. Without this certificate, you may find your property difficult to sell when the time comes.
How long does it take to install a downstairs toilet?
A straightforward downstairs toilet installation typically takes 7 to 10 days. This covers plumbing, electrical work, tiling, and fitting of fixtures. Jobs involving new pipework runs, structural work, or under-stairs conversions may take longer.
Can I convert my under-stairs cupboard into a downstairs toilet?
Yes – an under-stairs cupboard is one of the most common spaces used for a downstairs toilet installation. You’ll need a minimum of 70cm width, 130cm depth, and 2m of headroom at the toilet position. Costs typically range from £1,000 to £2,000 depending on how close the space is to existing waste and water supply. If no waste pipe is nearby, a Saniflo macerator system can be used as an alternative.
