Hi Hugh,
Thanks for your question. Drybase Flex was designed primarily for the application of plasters and tiles. We have not tested Drybase Flex in conjunction with plasterboard, so cannot recommend it for this use.
Membrane with black fleece on one side and grey fleece on the other.
Polypropylene
1.5 mm
1 x 15 m
Drybase Flex Membrane
Can be applied to damp substrates
Accepts plaster finish directly
No need for plugs (no unnecessary penetration of membrane)
A watertight low-profile sheet membrane for protection against dampness in walls without the need to drill and install plugs. The membrane is a 1.5 mm thick flexible polypropylene sheet with a fleeced surface on both sides. The two fleeces ensure good adhesion to the wall by means of Drybase Flex Adhesive, as well as the direct application of plaster to the face.
Drybase Flex Adhesive is a polymer modified cement-based product used to fix Drybase Flex Membrane to walls. It is supplied in powder form ready to be mixed with water, and applied using a suitable trowel.
Before Drybase Flex Adhesive can be applied, any structural defects on the substrate must be fixed. Clean the surface of the substrate to ensure maximum bonding of adhesive. Remove all surface laitance, loose particles, paint, etc. by means of wire brushing or light / wet / dry sandblasting or high pressure water jetting.
Note: Drybase Flex Adhesive should only be applied in conditions over 5°C.
Mix to the ratio 1 part tap water to 3.5 parts Drybase Flex Adhesive by weight (for 10 kg bags, add 2.9 litres of water). Add the Drybase Flex Adhesive to the clean tap water and mix thoroughly with a mechanical mixer until a smooth consistency is obtained.
Note: Use Drybase Flex Adhesive within 30 minutes of mixing. Once the adhesive is on the wall, Drybase Flex Membrane must be adhered to it within 10 minutes.
Spread the Drybase Flex Adhesive with a suitable trowel over the face of the wall to cover approximately 1 m2 at a time. The preferred adhesive thickness is 1 - 2 mm.
Offer the Drybase Flex Membrane up to the adhesive on the wall and use a trowel to apply gentle pressure spreading from the centre outwards. Make sure there is a 25 mm gap between the floor surface and the membrane (see the Floor-Wall Junction detailing below). Ensure that full contact is established between the membrane and the adhesive. Using a roller may be more suitable to achieve an even pressure.
Note: For details such as overlapping joints, corners, doors, and windows, please refer to the detailing diagrams beneath these instruction steps.
Remove any excess adhesive with a damp cloth before it sets and trim any excess membrane with an appropriate cutting tool.
After the adhesive has cured overnight, surface finishes can be applied such as bonding plaster or hardwall plaster; both are suitable for application prior to a skim finish.
Before Drybase Flex Adhesive can be applied, any structural defects on the substrate must be fixed. Clean the surface of the substrate to ensure maximum bonding of adhesive. Remove all surface laitance, loose particles, paint, etc. by means of wire brushing or light / wet / dry sandblasting or high pressure water jetting.
Note: Drybase Flex Adhesive should only be applied in conditions over 5°C.
Mix to the ratio 1 part tap water to 3.5 parts Drybase Flex Adhesive by weight (for 10 kg bags, add 2.9 litres of water). Add the Drybase Flex Adhesive to the clean tap water and mix thoroughly with a mechanical mixer until a smooth consistency is obtained.
Note: Use Drybase Flex Adhesive within 30 minutes of mixing. Once the adhesive is on the wall, Drybase Flex Membrane must be adhered to it within 10 minutes.
Spread the Drybase Flex Adhesive with a suitable trowel over the face of the wall to cover approximately 1 m2 at a time. The preferred adhesive thickness is 1 - 2 mm.
Offer the Drybase Flex Membrane up to the adhesive on the wall and use a trowel to apply gentle pressure spreading from the centre outwards. Make sure there is a 25 mm gap between the floor surface and the membrane (see the Floor-Wall Junction detailing below). Ensure that full contact is established between the membrane and the adhesive. Using a roller may be more suitable to achieve an even pressure.
Note: For details such as overlapping joints, corners, doors, and windows, please refer to the detailing diagrams beneath these instruction steps.
Remove any excess adhesive with a damp cloth before it sets and trim any excess membrane with an appropriate cutting tool.
After the adhesive has cured overnight, surface finishes can be applied such as bonding plaster or hardwall plaster; both are suitable for application prior to a skim finish.
It is important that joint details prevent the penetration of water. For joining two sections, an overlap is recommended of at least 50 mm width.
Apply Drybase Flex Membrane on top of the Drybase Flex Adhesive, leaving a 25 mm gap between the bottom of the membrane and the floor.
Apply Drybase Flex Adhesive up to the wall joint and 100 mm onto the abutting wall. Apply Drybase Flex Membrane up to the wall joint.
When plastering around a window, Drybase Flex Adhesive and Drybase Flex Membrane should both be applied up to and around the window frame and window sill.
Apply both the adhesive and membrane up to the door.
Hi Hugh,
Thanks for your question. Drybase Flex was designed primarily for the application of plasters and tiles. We have not tested Drybase Flex in conjunction with plasterboard, so cannot recommend it for this use.
Hi, First of all do you deliver to Northern Ireland. Secondly can I put Drybase flex membrane on a painted wall which has been sanded. Thank you.
Hi Jackie,
Thanks for your question. Yes, we deliver to Northern Ireland.
Please give us a call at 01403 210204 so we can offer the best in-depth advice on this particular project.
Will Drybase Flex Adhesive adhere to plaster and plasterboard?
Yes it will, as long as the plaster / plasterboard is unpainted.
Drybase Damp Resistant Plaster and Drybase Fast Set Plaster can be used to 'dub the wall out' (build it up to a smooth surface) prior to the application of Drybase Flex Adhesive.
Can I drill and insert fixings through Drybase Flex Membrane?
To fix through Drybase Flex Membrane carry out the following steps: Use a masonry drill bit to make a pilot hole through the membrane before drilling out the hole in the substrate fully. A masonry drill bit will reduce fibre entanglement.
For above-ground use, fill the fixing hole with Drygrip and then insert the wall plug and fixing. Drygrip Adhesive helps to protect the fixing from moisture. For below-ground use, fill the fixing hole with waterproof epoxy chemical anchor resin and then insert the fixing.
We advise using non-corroding materials like stainless steel screws in damp and salt-rich conditions.
What is the performance life of Drybase Flex Membrane?
Drybase Flex Membrane has passed independent testing on the following criteria:
Water tightness
Resistance to tearing
Resistance to impact
Tensile properties
Resistance to static loading
Visual Defects
Thickness and mass per unit area.
The above testing includes alkaline exposure to limewater as well oven testing to accelerate the ageing process. These tests are in line with tests carried out on other polypropylene membranes.
Here is the Drybase Flex Membranes description of durability:
'Under normal conditions of use, the product will provide an effective barrier to the transmission of salts, liquid water and water vapour for the life of the structure in which it is incorporated.'
What is the best way to terminate an application of Drybase Flex Adhesive and Membrane at the floor / wall junction?
Drybase Flex Adhesive and Drybase Flex Membrane can be applied to the wall to terminate 25mm above floor level to avoid wicking & the subsequent potential of bridging.
Alternatively, Drybase Flex Adhesive can be applied to waterproof the wall to just above floor level. Flex Membrane can then be applied to terminate 25mm above Floor level to avoid wicking & subsequent potential of bridging.
Another solution is to apply Drybase Liquid DPM to the floor and then lap it up the wall to meet the Flex Adhesive, however it is recommended to avoid applying Flex Adhesive over Drybase LDPM if possible.
Can Drybase Flex Adhesive be applied onto a sand:cement render with Renderguard Gold added?
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Can you dot and dab plasterboard over this product please?