Radon Protection Suspended Timber Floors

For many years ground floors of suspended timber construction have been used in houses and other low rise buildings.

Radon protection suspended timber floors. Sometimes the vent leads only to the wall cavity and not to the under floor space. Trying to locate the optimum position of the radon barrier in this case becomes problematic because it conflicts with the positions of periscope ventilation cavity trays and. Drainage connections to pre formed inspection. A bre guide to radon remedial measures in existing dwellings p a welsh bsc.

In situ concrete suspended ground floors precast concrete floor planks to ground floors radon protection provision of sump ventilators in compartment walls beneath suspended ground floors. For radon levels above 1200 bq m 3 it is often the only solution. See our fact sheet. Suspended timber floor because this area is often the major contributor to the indoor radon level.

Detailed protective measure workmanship and inspection radon proof barriers protecting suspended timber floors tanking to basements and cellars high water table slip or shear planes blinding reinforced slabs accessible thresholds condensation and cold bridges. Radon concentrations as far as they can and ideally to below the target level 100 bq m 3. Suspended timber floors should be well ventilated to. An active radon sump fitted with a fan is the most effective way to reduce indoor radon levels.

Nhbc standards chapter 5 3 drainage below ground. Occasionally passive sumps without a fan may reduce radon levels. Influence of radon measures on timber floors. Nhbc standards chapter 5 2 suspended ground floors.

Basic radon protection full radon protection 4. To identify a suspended timber floor look outside for ventilation grilles just above ground level. Sumps work best under solid floors and under suspended floors if the ground is covered with concrete or a membrane. Although principally appropriate for solid floors a sump can be used with a suspended timber floor if there is a layer of concrete or a membrane covering the soil beneath it.

In some cases blowing into the sump and pressurising the soil can also prove effective. If there are not any vents outside it may be a solid floor. Improving underfloor ventilation if part or all of the ground floor is of suspended timber construction improving underfloor ventilation may be an appropriate method for reducing indoor radon levels.