After Heavy Autumn Rain: 10 New-Build Defects to Check

Heavy autumn rain provides one of the first real tests of a newly built home. A property that appeared completely dry during the summer can suddenly develop leaking gutters, damp patches, standing water or drainage problems once prolonged rain and stronger winds arrive.

The wet and windy weather experienced across parts of the UK at the end of September may have already exposed problems in some new-build properties. These defects should be recorded and reported quickly, even if the water disappears once the weather improves.

Recent figures from the New Homes Ombudsman Service show that snagging-related enquiries have increased by 205%. With defects and poor complaint handling continuing to cause disputes between homeowners and developers, keeping clear evidence of leaks and drainage problems can be extremely important.

Here are ten areas new-build homeowners should check following heavy autumn rain.

1. Water Stains on Ceilings and Walls

Check ceilings, external walls and the corners of upstairs rooms for new marks, discolouration or bubbling paint. Pay particular attention to areas beneath roof valleys, chimney details, dormer windows and roof penetrations. A small mark should not be ignored simply because it has dried. Photograph the area, record the date and check it again during the next period of rain.

Water staining can indicate problems with roof coverings, flashing, seals or the way rainwater is being directed away from the property. The visible mark may also be some distance from the point where the water originally entered.

2. Leaks Around Windows and External Doors

Look around window frames, patio doors and external doors for damp plaster, peeling decoration or water collecting on internal sills. You may also notice cold draughts or staining around the edges of the frame.

Leaks can be caused by defective seals, poorly fitted frames or problems with the surrounding brickwork. Missing or incorrectly installed cavity trays and weep vents can also prevent water from draining away correctly.

Take both close-up and wider photographs so the developer can clearly identify the affected window or door. Do not repeatedly wipe the area clean without first recording the evidence.

3. Roof Tiles, Flashing and Roof Penetrations

Strong winds and driving rain can reveal problems with slipped tiles, poorly finished roof edges, damaged flashing and inadequately sealed vents. These areas should be inspected from ground level wherever possible. Do not climb onto the roof yourself. Use binoculars, a camera with a zoom function or arrange a professional drone inspection if you suspect a roofing defect.

Check whether any tiles appear uneven, broken or missing. You should also look for damaged ridge tiles and gaps around vents, pipes or other roof penetrations.

4. Gutters That Leak or Overflow

Gutters should collect rainwater from the roof and direct it towards the downpipes. During heavy rain, check whether water is spilling over the edge, leaking through joints or running down the external walls.

Overflowing gutters are not always caused by leaves or debris. Sections may have been installed at the wrong angle, joints may be defective or the guttering may not have enough capacity for the area of roof it serves.

Persistent water running down the brickwork can contribute to staining, damp and damage around windows and doors. Record the problem while it is raining if you can do so safely, as the defect may not be visible once the weather clears.

5. Downpipes and Rainwater Outlets

Follow each downpipe down the outside of the property and check where the water is being discharged. Look for loose connections, leaking joints and water collecting around the base. A downpipe should not simply release large volumes of rainwater against the wall or foundations. It should be connected to an appropriate drainage point or discharge into a correctly positioned gully.

Check for signs of soil erosion, splashing against the brickwork or standing water near the property. These can indicate that the rainwater is not being carried away effectively.

6. Blocked or Overflowing Gullies

External gullies and channel drains should remove water from patios, paths, driveways and other hard surfaces. Following heavy rain, check whether they are overflowing or surrounded by standing water.

Building debris, mortar, soil and other materials can sometimes be left within new drainage systems. This may restrict the flow of water even where the drain appears clear from above.

Photograph any overflowing gully and record how long the water takes to disappear. Repeated problems may require further drainage investigation rather than simply clearing the visible surface.

7. Patios, Paths and Driveways Falling Towards the House

Paved areas should be designed so that rainwater flows away from the property or towards an appropriate drainage channel. If the levels or falls are incorrect, water may collect against external walls, doors and air bricks. Inspect patios, paths and driveways immediately after rainfall. Pools of water close to the house or streams running towards a doorway may indicate a problem with the finished levels.

This can be particularly concerning where external surfaces have been installed too close to the damp-proof course. Raised ground levels can increase the risk of water penetration and may obstruct ventilation points.

8. Water Entering the Garage or Porch

Garages, porches and external stores are often among the first areas to show water penetration. Check around door thresholds, wall junctions, windows and the base of external walls. Water entering beneath a garage door may be caused by poor driveway levels, inadequate drainage channels or a badly finished threshold. Damp walls may indicate issues with the roof, brickwork or seals around openings.

Do not assume that regular water entry is acceptable simply because the area is not part of the main living accommodation. The cause should still be identified and corrected.

9. Standing Water in the Garden

Some temporary surface water can be expected after exceptionally heavy rain. However, large pools that remain for prolonged periods may indicate poor ground preparation, compacted soil or an inadequate garden drainage system.

New-build gardens can be particularly vulnerable where construction traffic has heavily compacted the ground. A thin layer of topsoil may conceal rubble, clay or other materials that prevent water from draining naturally.

Record the depth and approximate size of any standing water, together with how long it remains after the rain stops. This will provide much stronger evidence than photographing the garden once the water has disappeared.

10. Damp Around Air Bricks and External Walls

Inspect the base of the external walls for excessive splashing, staining or damp patches. Pay particular attention to air bricks, vents and areas where soil, turf or paving has been installed close to the brickwork.

Air bricks should not be obstructed by soil, paving or standing water. Blocked ventilation can contribute to moisture problems beneath suspended floors and within concealed areas of the property.

You should also check whether water is being directed towards the walls by nearby downpipes, driveways or garden levels. The visible damp may be a symptom of a wider drainage or landscaping defect.

How to Record Leaks and Drainage Defects

Rain-related defects can be difficult to demonstrate after the weather improves. Photograph and film the problem while it is happening, provided it is safe to do so. Include a wider image showing the location and a closer photograph showing the defect. Make a note of the date, approximate time, weather conditions and how long any standing water remained.

Report the problem to your developer in writing and retain copies of your emails, photographs and responses. If a repair is attempted, photograph the area before and after the work and monitor it during the next period of heavy rain.

Avoid relying entirely on telephone conversations. If you discuss the problem by telephone, send a follow-up email confirming what was agreed.

Should You Check the Loft After Heavy Rain?

If your loft is safely accessible, look for damp insulation, water staining, droplets or daylight entering through the roof. A musty smell or isolated patch of wet insulation can also indicate water penetration.

Do not walk across unsupported areas or disturb insulation unnecessarily. If access is difficult or you are unsure what you are looking at, arrange a professional inspection.

Thermal imaging may help identify differences in temperature and moisture patterns that are not immediately visible. It should be used alongside a physical inspection rather than treated as proof of a specific defect on its own.

Why Autumn Is an Important Time for Home Snagging

Some defects only become apparent when a property is exposed to sustained rain, stronger winds and lower temperatures. A home completed during the spring or summer may therefore develop new problems several months after the owner has moved in.

This is why home snagging should not be treated as a single visual check completed on moving day. Homeowners should continue monitoring their property and report new defects within the applicable developer and warranty periods.

A professional home snagging report provides a structured record of the defects found during the inspection. This can make it easier to report problems clearly, monitor repairs and retain evidence if a disagreement develops.

Professional Home Snagging Reports from Home Snagging UK

At Home Snagging UK, we provide independent snagging inspections for new-build properties across the UK. Our experienced inspectors check for poor workmanship, incomplete work, water penetration risks and other defects that may be missed during an ordinary viewing. Our inspections can include thermal imaging and drone photography where appropriate. This allows us to assess areas such as roofs and potential moisture problems without homeowners putting themselves at risk.

Following the inspection, you will receive a comprehensive home snagging report that clearly records the defects found. The report can then be submitted to your developer when requesting repairs. We provide pre-completion, post-completion and de-snag inspections. Whether you are preparing to collect your keys or have discovered problems after moving in, our team can help you understand the condition of your new home.

Contact Home Snagging UK to arrange a professional snagging inspection and receive an independent report for your property.

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