Leave nothing to chance 

When you’re ready to revamp an outdated bathroom, it can be tempting to rip everything out straight away. But the more organised you can be, the less likely it is that you’ll incur additional costs. These small projects have a tendency to drag on, so to ensure the contractor and crew are out of your hair as swiftly as possible, try to purchase everything before they start. This will ensure all goods are delivered as soon as they’re needed on site, avoiding unnecessary delays and cost overruns.

Think about the details you’d like to include and discuss all of them before work begins. For example, if you want a recess in your shower to hold shampoo and body wash, be clear about this from the outset, as it will be difficult and costly to install after

Plan for removal of existing fittings and finishes 

Before the work commences it’s important to be clear about who will be responsible for getting rid of the existing bathroom fittings and finishes. If your contractor has agreed to take care of this, make sure it’s included in their quote.

If it isn’t included, you’ll be responsible for getting rid of the items, which means you’ll need to budget for hiring a skip or disposing of the items at the local dump.

Double check your measurements

A common pitfall when renovating a bathroom is not ordering enough tiles. This can cause delays, particularly if the tiles aren’t stock items and have to be ordered.

Calculate the floor and wall areas separately and allow a minimum of 10% extra for wastage. When getting a quote for tiles, make sure the supplier includes grout, adhesive and tile trims, as these can add an unwelcome extra cost once you’ve committed to a particular design.

Not all finishes are created equal 

Certain finishes can be harder to fit than others. Take mosaics or unusually shaped tiles, for example – they’ll take longer to install and will therefore be more costly. It’s best to have all of your finishes selected and purchased before your contractor starts. That way, they’ll be aware of what you’re planning to use and will price for the job accordingly.

Similarly, marble or stone may need specialist detailing at the edges. The best way to finish edges is by having the tiles bevelled. This can be done either on- or off-site. You’ll need to discuss all of this with your tiler in advance, as it will have an impact on the price, but the difference in the finish will be worth every penny.

Plan your electrics 

If you’re planning layout changes to your bathroom, you’ll probably have to relocate lights and possibly light switches, so it’s important you don’t forget the cost of rewiring. If you’re having anything electric added or changed, you’re going to have to get an electrician in to upgrade the wiring.

This might be as simple a change as adding in a shaver socket, or as complicated as installing new light fittings on separate circuits. For example, it works well to have overhead lighting on one circuit and ambient cabinet or wall lighting on another. The cost for this kind of work will depend on the complexity of what’s involved.

Set aside a contingency 

It’s hard to get a handle on the full extent of the works until everything has been stripped out. Depending on the age of your home and its general condition, you might have to spend a lot on fixing or preparing your walls and floor.

For example, once the original floor finishes have been removed, you may find the surface isn’t perfectly even. To level it, the contractors will have to lay a special compound, and a change in floor level might even lead to doors having to be adjusted. Unforeseen extras like these will add to the cost.

Bespoke items cost more 

Anything that needs to be specially made is going to be more expensive than an off-the-shelf version. Unusually shaped shower screens or bespoke cabinetry, for example, will add to your renovation cost.

Custom-made items will also be on a longer lead time, so it’s important to flag this with your contractor early on to make sure there are no time delays or overruns

Don’t skimp on waterproofing 

Even if you’re not planning a wet room-style shower, you’ll need to waterproof the walls around a shower or bath. Moisture-resistant plasterboard should be used to create any shower enclosures. Alternatively, fibreglass can be used to cover the entire area.

Both of these methods are an additional cost, so even if you’re only replacing your existing sanitaryware, you should factor in your chosen material.

Plan the location of your shower pump 

When you’re choosing a pump for your shower, make sure you understand what you’re getting and where it’s going to be located. Are you going for a pressurised system with all of your water under pressure? For this you’ll need to install a new water cylinder, as well as the pump.

All pumps make noise, but some are a lot louder than others, so you might want to really think about where you’re locating yours. If you’re doing a larger renovation and can decide on where to put the water cylinder, it’s worth locating it away from the bedrooms. All of these decisions will have a bearing on costs.