Barriers (membranes) which are impermeable to radon can be laid across the footprint of a building during construction. It is important that these are installed by trained specialists, and not general groundworkers, as any gaps or splits in the material will allow the gas to pass through and can render the membrane useless. The current Building Regulations require newbuilds in certain parts of the country to incorporate radon protection. Approved Document C is currently being rewritten and the revised version is likely to require all newbuilds and extensions to include basic radon protection.
The Radon Council advises that all property purchases request a radon screening test to be carried out before exchanging contracts. It is often the case that a prospective purchaser will conduct a damp and timber survey before going ahead with a purchase, and it would be prudent to also conduct a radon test. If the test result is close to or exceeds the Action Level, it may be appropriate to negotiate with the vendor to pay all, or part, of the cost of remediation.
As with most things in life, you get what you pay for. A test using a detector posted to you for placement under instructions should not exceed £50 per house. After the given test period, you post back the detector and the company concerned subsequently posts you full written details on a confidential basis.
If you have a level near or above the "Action Levels" quoted above, depending on the nature of the property, remedial action may have to be considered. The Council's list sorts out the various kinds of service on offer. Remedial work charges will obviously vary according to the size and construction of the property.
Written schedules outlining the reasons and nature of work and including costs should be offered for all work quotations. In the past, some consumers have obtained details of the recommended remedial work from a reputable Company and have then used these details and had the work done by inexperienced operators. As a consequence several organisations now make a charge for such a schedule. You should check that this is refundable if the company is entrusted with the work.
Be advised that no one universal solution exists for radon treatment in existing buildings, therefore experienced contractors will be able to select a suitable method for your property. The Radon Council strongly recommends that radon detection and remedial work should be undertaken by persons trained and experienced in such work.
The current situation in the UK is that legislation exists for "new build" housing in defined areas for domestic occupiers and for employees in the workplace anywhere in the UK. For the much larger stock of older homes however, no resources are available for remedial work.
There has been a considerable effort funded by the tax-payer to identify problem regions now designated as "Affected Areas". The lack of financial resources when readings above the 200 Becquerel level (Action Level) are found in homes means that a large proportion of houses or flats needing remedial work are left in their original state, This is clearly unacceptable from the human health point of view and several proposals have been put forward to deal with the problem. Discretionary grants although available have seldom been awarded.
The Radon Council has proposed the one UK system that avoids unnecessary bureaucracy and initiates remedial work with the provision of the necessary funds when that is clearly required. The BRE and Council are in broad agreement that with current prices the average costs of remedial action for a domestic house will be up to £750 - £1,500. A few will cost more and some less. The proposal is that at the time of conveyancing (i.e. transferring ownership of a property), the results of a short term test (or preferably a longer term test if available) for radon be exchanged between the solicitors for the buyer and seller.
Should any remedial work be necessary then arrangements can be agreed for financing the work from the sale proceeds and for the mortgage loan being used for the purchase. The same kind of procedure would apply when tenancy documents are being prepared except that the onus would clearly be on the landlord to provide a property clean and fit for healthy occupation. These proposals would apply anywhere in the UK. They would also lead to an increasingly accurate picture of radon distribution throughout the country if the data could periodically be made available.
Other methods have been suggested or tried. For example, an indemnity insurance policy, or financial sum being retained as a kind of Bond. Such actions are not required if the results of a radon test are known. A Bond has the disadvantage of tying up sellers' money together with associated costs.
For your own peace of mind a test costing about £ 50 may well be a good investment. Keep a written record of the results against the day when you decide to sell. Only if your home requires remediation are you faced with a decision on taking action to reduce the level of radon gas. After consulting one of the remedial contractors on the above list, you may have a better idea of total costs and whether you can afford them.