A new-build house inspector, known as a snagger, is urging owners to check their property thoroughly after picking up the keys, as he has found some strange things in people’s homes.

“Finding things like sandwiches, food waste and bottles is, unfortunately, fairly common,” says professional snagger Chris Greenwood, who identifies issues with the quality of the home after the building work has been completed.

He says he has even found bottles of urine, which “tend to be under baths or under shower trays”.

“It makes you wonder what else has been missed,” he adds.

Snagging aims to identify defects or problems or something that is broken, damaged, not fitted properly or looks unfinished. Owners typically have a two-year period to identify them and flag to the house builder to correct.

An industry body insists confusion over snagging issues has given builders a bad reputation.

The National Federation of Builders (NFB) said traders do care about building to a high standard and that some snagging is inevitable.

Chris says his snagging inspection service costs between £300 and £600, depending on the size of the property.

He provides an independent report to the homeowner, who can use it to raise any issues with the developer.

Chris says his finds can range from the mundane, such as bumpy plasterwork, to the bizarre, which includes socket plates with no wiring behind them.

However, he also adds that not all houses he inspects have issues and some have been built to a “very high quality”.

The BBC joined him on his latest inspection at a new-build house in Lincolnshire, where he immediately found a mouldy sandwich in the loft.

“It’s embarrassing because [it shows] no one has been up and looked at those items prior to completion,” he says.

“It’s a really, really quick check. It took me the time to get my ladder out and popping my head into the loft to identify those issues.

“It doesn’t give the customer the confidence that other things have been checked if that’s the first thing I am putting on my report.”

Chris also discovered the patio doors were not sufficiently sealed, letting in cold air, and identified a number of issues he put down to poor workmanship or materials.

Fellow inspector Kelly Skidmore says the snagging industry faces “significant resistance” from developers who are “often reluctant to have independent third-party professionals scrutinising their workmanship”.

He says his inspections typically uncover between 60 and 80 problems per property.

Many are minor cosmetic issues, but he says he has also uncovered serious failings such as errors in “fire-stopping” – special measures to stop the spread of fire between different parts of a building.

The New Homes Quality Board was set up to help customers through the process of buying new homes.

CEO Emma Toms believes owners have a right to expect their home to be of a high standard and should not need to use snaggers.

However, she says there has to be an element of understanding about the conditions homes are built in.

“They are not built in sterile air-conditioned factories, they’re built outside, usually in a muddy field, in all weathers by up to 200 people,” she says.

With that in mind, should new-build owners be less picky and more understanding about the potential problems they could uncover?

“I am not being picky,” Chris adds.

“It’s a brand new house. It should be of a high standard at handover.

“If you were to buy a brand new car and it was full of dents, you would question why. So, no. The developer needs to pick these items up, identify them and rectify them in a timely manner.”

According to the Homeowners Alliance, this is what new-build owners should look for when moving in.

• Roof tiles are one of the most common issues found on snagging lists.
• Ensure outside walls, gates and fences are sturdy, along with any locks.
• Pipes: Check water can flow through and drain.
• Check brickwork and paintwork on the outside is to a good standard.
• Check ground is even on driveway and garage doors and windows are sturdy.
• Check windows and doors inside to make sure they are fitted properly.
• Ensure stairs are strong and don’t creak when using them.
• Make sure kitchen fittings are installed properly and test appliances and taps.
• Ensure the grouting in the bathroom has been done properly and that tiles have been fitted correctly. Check the taps and shower work properly.
• Check for cosmetic issues, such as paintwork, carpets laid properly and skirting boards are not loose.
• Turn the heating on and make sure radiators work properly.
• Flush all toilets to check they work and run every tap to make sure they work.
• Check all the plug sockets work and are fitted correctly to the wall.

The large number of people working on one property can be part of the problem, according to Rico Wojtulewic, head of policy at the NFB.

He believes sub-contracting can lead to confusion among workers, who he says can lose track of who is checking what.

Rico says there is “potential for human error” with any house build but confusion between smaller snags and larger structural problems, which he says are generally less common, has played a part in giving house builders a bad reputation.

He adds: “They really do care about the builds they’re doing and recognise that people are making the biggest purchase of their life.”

Kate Hatton, from Warwickshire, has used the same professional snagger twice and believes it is important to seek professional advice.

“You’ve got the backing of someone in the trade who can say ‘no that isn’t right’.”

Her snagger found issues ranging from small cosmetic problems to missing panels and a vent on the wall that was not installed properly, running the risk of causing water to come into the house if not rectified.

“I think you always expect something but I was surprised by some of them,” Kate says.

Both Chris and Kelly believe a lot of the snags they find are as a result of skills gaps in traders, a feeling echoed by the building trade.

Rob Sanderson, senior contracts manager at Lincolnshire construction company Gelder Group, says he has seen a change in workers.

He feels more experienced tradespeople “focused on attention to detail” are retiring and not enough new people are coming into the construction industry.

However, he agreed with the NFB, saying good builders do care and “in the first instance, buyers should give the developer the chance to rectify any snags,” rather than seeking external help.