Buying a home and checking out all the potential problems you could face can be a tough process, even if you are buying a new build.

A new build is a home that has been recently constructed and has not had anyone live in it yet.

In theory, that should mean problems should be at a minimum, but there are a number of hidden red flags related to drainage that could prove costly.

Andrew Pemberton, a chartered building engineer from The Professional Snagging Company, has revealed the issues people need to check for.

He said: "Water damage caused by poor drainage is one of the most expensive and easily missed problems in modern homes, but with the right know-how, many of these issues can be spotted early."

5 drainage red flags new-build buyers need to look out for

Water pooling near your walls after it rains

After a downpour, take a walk around the outside of the property to see how well the rainwater is draining away. If the water stays near your home, there could be issues.

Andrew explains: "Water should run away from your property, ideally towards a drain or soakway.

"If you notice this isn't happening and the water is sitting against the base of your home, this water could be seeping into the foundations. Over time, this can cause damp and subsidence."

Downpipes that lead nowhere or spill into the soil

Guttering and downpipes are supposed to move the water away from your home, but the issue with new builds is that sometimes they aren't connected correctly in the construction process.

It is advised for buyers to look where their downpipes are emptying, and if they are going onto your patio, grass, or base of the wall, then there could be a problem.

Andrew adds: "Every downpipe should be properly connected and directed away from your home into a gully or underground drain, if it isn't, then this will compromise the structure of your home over time."

Musty smell in the bathroom

If your bathroom smells a bit musty or your tiles feel uneven, that could mean water might be leaking underneath.

This is often caused by poor drainage in shower trays or wet rooms, and it’s more common in new builds than people think.

Over time, this can lead to "mould, floor rot and expensive repairs", according to Andrew.

Water is taking too long to drain in the shower

When you turn on the shower, pay attention to how quickly the water drains. If the water is slow to drain or pools in the corners, it may be more than just a blocked drain.

Andrew explains that water shouldn't linger for minutes at a time, which could mean the tray or wet room floor isn't sloped properly.

Your garden slopes towards the home

A slight incline in your garden towards your home can play a big role in where water ends up.

Andrew says: "Even a gentle slope towards your home can direct litres of water back to the foundations every time it rains.

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"Your patio may look perfect, but if you have even the smallest of slopes that traps water against your home, it doesn't take long for it to create problems under the surface."

What to do if you spot drainage red flags in your new build?

If you notice any of these issues, it's important to report them to your housebuilder as soon as possible, ideally within your snagging period or warranty timeframe.

Andrew warns, "If drainage issues are left unresolved, they can worsen quickly and lead to major repairs that might not be covered by your warranty if too much time has passed."