Jewson building materials can make sure you have everything you need to not only install a damp proof course, but to complete the job from start to finish. The paving/ground level should always be at least 75mm below the DPC. Anything less than that is just asking for trouble.* For external walls the DPC should be applied 150mm a fresh bed of mortar, completely free of projections that may puncture the material or impede the material from lying flat. When joining two pieces of DPC they should be lapped over each other by at least 100mm. If renovating after a pre-existing damp problem, consider installing fresh sawn & carcassing timber to replace rotten stud work and battens. It should be noted that breaches of the 150mm rule are the sort of thing that is noticed by Surveyors when valuing a property and it can lead to a reduced valuation or a requirement for remedial work to be undertaken.

The DPC also features an embossed finish to make mortar adhesion better. How to install a DPC membrane The reveal should be protected throughout its width by a continuous DPC. The width of the DPC should be sufficient to be fixed to, or overlap, the frame and fully protect the reveal. For very severe exposure conditions, rebated reveal construction or a proprietary closer, suitable for the conditions, should be used.The polyethylene foam insulation used in ARC Insulated DPC has a thermal conductivity of 0.039W/mK. A cavity tray should be provided to direct any water that enters the cavity to the outside. The cavity tray should fully protect the opening. DPC (Damp proof course) is used when a physical barrier is required to prevent moisture travelling up building walls. Most existing constructions should have a form of DPC already in situation, however this product will be required for new wall constructions to prevent an issues with rising damp.

A DPC should be provided a minimum 150mm above adjoining surfaces and linked with the DPM in solid floors. The Building Regulations require at least 150mm between the dpc and the ground or any paving. This is what is known as 'Best Practice'. However, there are situations where it is just not possible, or practical, to maintain this regulation. On professional work, and new build projects, every possible effort should be made to ensure the 150mm rule is not breached, but, for small, domestic projects, such as a driveway or patio, there are cases where keeping the paving to 150mm below dpc would involve a huge amount of work that cannot be justified. In such cases, the 150mm rule can be 'bent' a little, but with the following provisos...Unfortunately, We Cannot Guarantee Next Working Day - you will be notified if we can't fulfill this. Use of an insulated cavity closer would have prevented these last 2 problems. For more information about preventing cold bridges, refer to our Registered Construction Details. Damp proofing membranes protect different parts of a structure from damage arising from damp, including mould and mildew, and the risk of rotten timber. Preformed stepped cavity trays should be provided above the roof surface and linked to the roof upstand or flashing to ensure any water penetrating into the cavity does not enter the enclosed area.