I think my property has radon, what should I do?

So you’ve heard about radon, but what exactly is it?

When it comes to dangerous gases, it’s not just carbon monoxide you have to worry about.

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Radon is a colourless and odourless radioactive gas that is created by the radioactive decay of small amounts of uranium that occur naturally in all rocks and soils. Which all sounds a bit sci-fi and scary, doesn’t it?

And it is a concern as radon emits radiation that is a risk to health, causing damage in living tissue that can increase the risk of cancer.

Radon is found everywhere because it’s formed by the uranium in all rocks and soils. Usually, the levels are low enough that the risk to health is very small – although there is no such thing as zero risk when it comes to radon. You can see the level of radon in an area on a radon map – the darker the colour, the more chance there is that there is a high radon level in that area or building.

Is your property affected by radon?

If you’re in the process of buying a property, your survey may be the first time that you’ve heard about radon. Hearing that your dream new home or great new buy-to-let is in ‘a radon affected area’ can be very worrying, as no one wants to live in a radioactive zone!

The UK Health Security Agency has a radon map, so you can see the areas of the country most affected by radon.  

If your survey has flagged potentially high levels of radon, it is definitely worth getting an in depth radon report before you go any further with the purchase. 

  • Long-term testing. A radon detector is left in the living room and bedroom (areas in which residents spend the most time) for 3 months, so that seasonal changes can be accounted for to give a more accurate report on possible exposure levels. It may be that the seller has this report already from when they bought the property and is willing to share. If not, it’s unlikely that they’d be willing to delay the sale while a full check was undertaken, so a ‘radon bond’ is a good idea
  • Short-term screening. The radon detector is only left in place for 10 days. While it won’t account for seasonal changes, this should provide enough detail to base a decision on

Checks are fairly cheap so they are not at all prohibitive to get if your initial survey flags this as something you want to look into. 

What is a radon bond?

High levels of radon doesn’t necessarily mean that you should pull out of the sale. This is entirely up to you and what you feel comfortable with, of course. But if you are able to afford the mitigation works and you’d be comfortable with the property once the updates are made, you can certainly go ahead.

However, if you do decide to go ahead, it’s worth looking into getting a ‘radon bond’, which is an agreement between the buyer and the seller and their solicitors. It means a sum of money, agreed upon by both parties involved, is held by the solicitor for a set period of time while further testing is carried out. 

This way, those 3 month long tests won’t hold up the transaction (which can take several months already!) and the reasonable cost of the remediation work will be covered. The UK Radon Association recommends £2,500 to cover these costs, with a deadline of 6 months post completion to use it, which allows enough time for a thorough 3 month test and to get quotes for any remedial works.

Should the test come back low, with no further action required, the money is released from the bond back to the seller.

What are radon mitigation measures?

If the property you are looking to buy (or sell – carrying out these works will make it easier for you to sell!) has high radon levels, there are a couple of things you can do:

  • Improved ventilation. Many homes have suspended ground floors, which means there is space between the floor and the ground below. Good natural ventilation here can help reduce radon, but you can install a fan which will either blow air in or extract air from the ventilated area, to further lower the radon levels. A fan can also be installing in the roof space to blow fresh air into the building
  • Radon sump. This is a small void excavated beneath a building, fitted with a fan, for the purpose of collecting radon before it enters the building. They work best under solid floors or suspended floors if the ground is covered with concrete or some other kind of membrane

You will need to make sure that these measures have been carried out and that your property is completely safe before you rent it out. Ensuring your tenant’s safety is a key landlord responsibility, this is why checks like Gas Safety and EICR and the installation of fire and carbon monoxide alarms are legal requirements.

It’s worth noting that your lender will also be notified about this development. It may not affect your mortgage at all, but the lender needs to be aware so they can make an informed decision. Getting a mortgage can be an overwhelming process, especially if it’s your first, so make sure you have a good team on your side that you can turn to with your questions! Our Mashroom Mortgages team give their advice completely free of charge, so book a call today if you’re looking to start your mortgage journey.  

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