How should DPC be laid?
Lay the DPC on a full even bed of fresh mortar in one continuous length, for the full width of the leaf. Provide at least a 100mm overlap at any joint or corners. The DPC must not obstruct the cavity. Ensure the external edge of the DPC is visible and not bridged by mortar when completing pointing of the mortar joint.
Should DPC be laid on mortar?
DPCs should:
be fully bedded on mortar where required by the design, or where the building is over three storeys in height. at ground level, generally be a minimum of 150mm above finished ground or paving level.
How do you lay a DPM membrane?
How do you Install a Damp Proof Membrane?
- Surface Preparation. Cutting the Membrane To Size.
- Surface Preparation: Clean the substrate to remove all loose debris and organic matter.
- Cutting the Membrane to Size:
- Membrane Jointing:
- Sealing Around Protrusions:
- Fitting and Fixing the Membrane to the Wall:
How high should DPC be above ground?
A damp-proof course is a barrier, usually formed by a membrane built into the walls of a property, typically 150 mm above ground level, to prevent damp rising through the walls.
How far below DPC should foundations be?
A minimum 225mm clear cavity below the DPC should be maintained. When specialised foundations are used, including those for timber framed buildings, the minimum clear cavity depth may be reduced to 150mm below the DPC, provided that weep holes and other necessary measures are taken to ensure free drainage.
Do I need a cavity tray at DPC level?
There isnt normally a cavity tray at dpc level, unless in instances where the likes of a Radon Barrier is required, which should overlap inner wall, cavity and outer wall. You would then need a cavity tray above with weep holes.
How far below damp course should paving be?
The external surface should be 150mm (6 inch) below the line of the damp proof course. Hope this helps from David at DMA Associates Preston. Any driveway should be at least 150mm/ 6 inches ( two course bricks) or more from damp course.
How much should DPM overlap?
The purpose of DPM
Care must be taken to ensure a) there are no holes or tears in the sheet that could allow water penetration and b) there is a sufficient overlap of sheets by at least 150mm should more than one sheet be required.
What is difference between DPC and DPM?
The damp proof course may be horizontal or vertical. A DPC layer is usually laid below all masonry walls, regardless if the wall is a load bearing wall or a partition wall. A damp-proof membrane (DPM) is a membrane material applied to prevent moisture transmission.
How far should concrete below damp course?
Post your job to find high quality tradespeople and get free quotes. The external surface should be 150mm (6 inch) below the line of the damp proof course. Hope this helps from David at DMA Associates Preston. Any driveway should be at least 150mm/ 6 inches ( two course bricks) or more from damp course.
Can you put gravel above DPC?
A land drainage pipe, usually a perforated plastic type, is laid at the base of the channel, connected to the SW drainage system at a convenient point and covered with a clean gravel to a level no higher than the dpc. The walling may be protected by a drainage composite or tanking.
Should you fill the cavity below DPC?
A clear cavity for at least 225mm below dpc should be maintained. When specialised foundations are used, including those for timber framed buildings, this depth may be reduced to 150mm below dpc if weep holes are provided and other necessary measures are taken to ensure that the cavity can drain freely.
Is there an alternative to a cavity tray?
Led-a-flex is a lead substitute manufactured with a base of EPDM and aluminium expanded metal.
Do I need wall ties below DPC?
It depends on how high the dpc is off ground level or how deep the foundation is in the ground, if possable use a trench block in the ground or if using concrete blocks use wall ties every two course (450 high & 900 long) then fill cavity with a lean mix of concrete to a level of 150mm below dpc.
Does patio have to be 150mm below DPC?
The standard arrangement. Paving is kept at least 150mm below the dpc and slopes away from the wall at around 1:60. This may need to be increased to 1:40 for some ‘difficult to drain’ pavings, such as riven flags, or may be decreased for well-draining pavings, such as blocks or plain concrete.
Does DPM go under or over DPC?
Whilst we are on the subject, it is normal that the DPM overlaps with the DPC (Damp Proof Course). The DPC is normally laid within the bed joint of the brickwork or blockwork, primarily to stop ground damp from rising up the walls by capillary attraction.
Does DPM need to be taped?
DPM Installation
When DPMs overlap you should use DPM tape to seal the joints. We sell both single and double sided DPM tape. Your DPM always needs to be continuous with the damp proof course (DPC) in the walls etc.
What are the 3 types of DPC?
The following are different types of DPC and their thickness used in construction,
- Damp Proof Course Injection.
- Mortar Injection Damp Proof Course.
- Electro Osmotic Damp Proof Course.
- Damp Proof Membrane Course.
How far below DPC should soil be?
150mm
The Building Regulations require at least 150mm between the dpc and the ground or any paving. This is what is known as ‘Best Practice’.
Why is 150mm below DPC?
The 150mm below DPC regulation is stipulated to prevent ‘splashback’ of moisture (ie rainwater hitting the ground and ‘splashing’ back up over the DPC. It is highly unlikely that having a DPC only 60mm above external ground level will have any detrimental effect on your property.
How far should soil below damp course?
150 mm
It should be at a height of 150 mm above ground level to comply with Building Regulations. Ideally you should instruct a reputable builder to undertake limited exposure works to check the position of the damp course and ground levels around the property should be reduced to 150 mm below damp course height.
Do you use brick ties below DPC?
Usually the brick ties are used every six courses of bricks(2 courses of blocks) above the dpc as normally there is less than 3-4 cources below.
Can I use DPC as a cavity tray?
The answer is a resounding “Yes”.
As stainless steel is the nobler of the two materials, the more active material, zinc, will corrode. In brickwork cavities, DPCs and Cavity trays will almost always be in close proximity to stainless steel products such as Masonry Support, Wall Ties, Lintels etc.
Do you always need a cavity tray?
Cavity trays are only required at roof abutments where the abutment wall becomes an inner wall below the roofline. Open porches and car ports are not habitable spaces, and therefore are not required to have cavity trays.