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New-build home inspection: what we check before you get the keys

2026

You bought a home off-plan. After two years of building work, the developer finally calls: the house is finished and they want you to come and sign the handover. It is a happy day, but it is also the moment when you have the most at stake, because anything that isn’t noted that day is much harder to claim later.

That is why, before you sign, an architect inspects the home for you, top to bottom, and gives you a report listing every defect so the developer repairs them before handing you the keys.

1You buyoff-plan2Worksabout two years3Noticeyou get a date4Inspectionwe go in5Repairsbased on our report6Keysall in order
1You buyoff-plan2Worksabout two years3Noticeyou get a date4Inspectionwe go in5Repairsbased on our report6Keysall in order
The best time to call us: once you have a handover date, and before you sign.

What we check

We check everything that can be seen, touched and tested. It isn’t a quick look: we open every tap, test every socket and close every window.

123456781Structure and façadecracks, damp patches2Walls, ceilings and floorsflat, straight and well finished3Doors and windowsclose properly, no gaps4Electricsevery socket, light and the fuse box5Plumbing and drainspressure, leaks and smells6Kitchen and bathroomstaps, fittings and sealant7Heating, cooling, hot waterheat pump and air conditioning8Terrace and poolfalls, filter, lights
123456781Structure and façadecracks, damp patches2Walls, ceilings and floorsflat, straight and well finished3Doors and windowsclose properly, no gaps4Electricsevery socket, light and the fuse box5Plumbing and drainspressure, leaks and smells6Kitchen and bathroomstaps, fittings and sealant7Heating, cooling, hot waterheat pump and air conditioning8Terrace and poolfalls, filter, lights
A complete inspection, from the roof to the pool.

1. Structure and façade

Cracks in walls and ceilings, cracks in the façade, damp stains and leaks. With the thermal camera we also see where insulation is missing or there are thermal bridges.

Fachada de vivienda con humedad en la base del muro
Damp rising through the base of the façade. Photo: Unité Arquitectura.

2. Walls, ceilings and floors

That they are flat and straight, with no dents, waves or hollow or cracked tiles. We look with raking light, which reveals what you can’t see head-on.

Rincón de una vivienda nueva iluminado con luz rasante
Raking light shows the waves in the plaster in a corner. Photo: Unité Arquitectura.

3. Doors and windows

That they open and close properly, do not rub, have even gaps, that the shutters go up and down and that no water gets in. The thermal camera also shows air leaks around the frames.

Ventana de dormitorio en una vivienda nueva
Windows: we check that they open, close and seal properly. Photo: Unité Arquitectura.

4. Electrics

We test every socket with a tester, the consumer unit and the RCDs, every light point, the doorbell, the entry phone and the TV sockets. In the consumer unit, the thermal camera picks up connections that are overheating.

Enchufes en una pared de vivienda nueva
We test the sockets one by one. Photo: Unité Arquitectura.

5. Plumbing and drainage

Pressure and flow at every tap, leaks, drains that empty properly, traps and no bad smells. If there is underfloor heating, the thermal camera traces the pipes and gives away any leak.

Ducha de un baño de vivienda nueva
In the shower we check the falls, the sealant and that it drains well. Photo: Unité Arquitectura.

6. Kitchen and bathrooms

Taps, firmly fixed sanitary ware, shower screens, silicone seals and units. Around shower trays and baths we measure the damp in the wall.

Moho en el techo de un baño
Mould in a poorly ventilated bathroom. Photo: Unité Arquitectura.

7. Heating, cooling and hot water

That the heat pump, the air conditioning and the water heater work, and that the units are properly installed.

Termo de aerotermia en una vivienda nueva
Heat pump water cylinder: we check the installation and that the paperwork is complete. Photo: Unité Arquitectura.

8. Terrace, roof and pool

Falls so water does not pool, waterproofing, railings, and in the pool the shell, the filter system, the lights and any leaks. We check the ceilings below for damp.

Terraza de vivienda nueva con agua encharcada
Standing water on a terrace: the fall does not take the water to the drain. Photo: Unité Arquitectura.

9. Paperwork

That what has been built matches the specification in your contract, and that you are given the paperwork: first occupancy licence, installation certificates, energy certificate and guarantees.

Caja de porcelánico con su etiqueta
The label on the box of porcelain tiles, to compare it with the specification. Photo: Unité Arquitectura.

What we use to check

As well as looking, touching and testing, we bring three instruments that reveal what cannot be seen with the naked eye.

Thermal camera

It shows the temperature of every point on walls, ceilings and floors. That is how we find areas without insulation, thermal bridges, air leaks at windows and hidden damp, which shows up colder than the rest.

Cámara térmica mostrando en su pantalla la imagen de temperaturas
Termografía de dos edificios: el aislado se ve frío y el que no tiene aislamiento pierde calor por toda la fachada
A thermal camera in use and the thermography of two buildings: the insulated one barely loses heat, while the uninsulated one loses it across the whole façade. Photos: Minea Petratos and Passivhaus Institut, Wikimedia Commons (CC BY-SA 3.0).

Moisture meter

When we see a stain, or the thermal camera shows a cold spot, we check it with the moisture meter. That way we know whether it really is damp and how much, and we record it in the report with its reading.

Medidor de humedad apoyado en la base de una pared
Humedad bajo el vierteaguas de una ventana
With the moisture meter we check whether a stain is wet or old: on the left, a reading at the base of a wall; on the right, damp below a window sill. Photos: Unité Arquitectura.

Electrical installation tester

We test the sockets with a tester that shows whether they are wired correctly and earthed, and we check that the RCDs trip when they should.

Comprobador conectado a un enchufe para probar el diferencial
Comprobador multifunción de instalaciones eléctricas
A socket tester and a multifunction installation tester. Photos: Skatebiker (CC0) and Santeri Viinamäki (CC BY-SA 4.0), Wikimedia Commons.

When thermography works best

The thermal camera needs a difference of about 10 ºC between inside and outside. In winter that is easy; in summer we measure first thing in the morning or with the air conditioning on for a while beforehand.

Real defects we have found

These photos are from one of our inspections of a new-build home. None of these defects is serious, but they all need repairing before handover, and that is much easier to get done if they are in writing on the day.

Fisura en la pared justo encima del marco de una puerta
Puerta con la holgura superior torcida respecto al marco
A crack above a door frame, and a door leaf out of square: the gap at the top isn’t even across its width. Photo: Unité Arquitectura.
Rincón de pared con el enlucido irregular visto con luz rasante
Manchas en la pintura de la pared de la escalera
Cables colgando del techo en un punto de luz sin terminar
With a torch held against the wall, waves in the plaster show up. Also stains on the staircase and an unfinished light point. Photo: Unité Arquitectura.
Equipo de aerotermia y depósito de agua caliente en un sótano
The systems are switched on and tested, like this heat pump with its hot water tank. Photo: Unité Arquitectura.

How we do it

  1. You send us the paperwork. The contract, the specification and the plans. That way we know what you should be getting.
  2. We visit the home. About two or three hours, depending on the size. If you like, you come with us and we explain as we go.
  3. We give you the report. Every defect with its photo, where it is and how important it is. Written so that anyone can understand it, including the developer.
  4. You give it to the developer. You attach it to the handover record, or we send it for you, so they repair it.
  5. We check again. When they say it has been fixed, we come back and check that it really has.

Sign the handover “with reservations”

If there are defects when you receive the house, don’t sign a record saying everything is fine. Write on it that you accept it with reservations and attach the report. It is your best proof that the defects were there from day one.

What the law says

Spain’s Building Act (Ley de Ordenación de la Edificación) protects the buyer of a new home for years, depending on the type of defect:

Finishespaint, scuffs, trims1 yearHabitabilitydamp, systems, insulation3 yearsStructurefoundations, columns, beams, slabs10 yearshandover13510 years
Finishespaint, scuffs, trims1 yearHabitabilitydamp, systems, insulation3 yearsStructurefoundations, columns, beams, slabs10 years
Guarantee periods from handover (article 17 of the LOE).

Watch out for one detail: once damage appears, you have two years to make your claim. The sooner it is documented, the better.

What if there are lots of defects?

Usually the developer carries out the repairs. But if they don’t, or the defects are serious, the path is still straightforward and we take it with you:

  1. Written claim. A certified letter (burofax) to the developer with our report and a deadline for repairs.
  2. Expert report. If needed, we turn the inspection into an expert report, with a valuation of what each repair costs.
  3. With a lawyer. We work with lawyers who handle the legal side. We defend the technical side, in court too if it comes to that.

How much does it cost?

For a normal-sized home, €350 + VAT. If it is larger or has a pool and garden, we give you a fixed price before we go, with no surprises. It almost always costs far less than a single one of the defects we find.

About to receive a new home?

Write to us as soon as you have a handover date. With a week’s notice we have time to read the contract and arrange the visit. We also inspect homes that have already been handed over, if problems have started to appear.

You will find all the details on our service page for new-build home inspection. You can write to us from the contact page or on WhatsApp at +34 633 39 85 44.

Cover photo: Mark Owen Wilkinson Hughes on Unsplash. The photos of each section and of the damp are ours, from real surveys and inspections; the photos of the equipment (thermal camera and electrical testers) are from Unsplash and Wikimedia Commons, credited under each one.

Further reading