EducationWindmill Primary School
Nottingham, NottinghamshireHot Melt
05Waterproofing system
Hot Melt Waterproofing
Hot melt is a rubberised bitumen membrane applied hot and fully bonded to a concrete deck. Because it bonds completely, water cannot track between membrane and deck, and minor damage self-heals. It is the standard choice for structural waterproofing beneath podiums, green roofs and inverted build-ups.
- Bond
- Fully bonded, no lateral water tracking
- Thickness
- Nominal 6 mm in two coats
- Testing
- Electronic integrity testing before loading
- Design life
- Matched to the structure above
About Hot Melt Waterproofing
Hot melt is specified where a failure would be effectively unrepairable. Once a podium deck is loaded with paving, planting and services, finding a leak in a loose-laid membrane is close to impossible. A fully bonded system means any water that does get through appears directly below the defect, so it can be found and fixed.
The membrane is applied in two coats with a reinforcing fleece between them, to a nominal six millimetre thickness. It is inherently self-healing at ambient temperature, so small punctures from follow-on trades close themselves rather than becoming a defect.
We electronically integrity test every hot melt installation before any protection layer or landscaping is loaded, and we invite the main contractor to witness it. That gives you documented sign-off at the one moment in the programme when a defect can still be reached.
Best suited to
- Podium decks and buried roofs
- Green and blue roof build-ups
- Inverted warm roof arrangements
- Any deck over occupied space
Sectors we install it in
Typical build-up
Section / outside in- 01
Surfacing
Paving, planting, ballast or podium build-up
- 02
Thermal insulation
Extruded polystyrene in an inverted arrangement
- 03
Protection layer
Root barrier and protection board
- 04
Hot melt membrane
Two coats, reinforced, nominally 6 mm, fully bonded
- 05
Concrete deck
Primed and prepared, falls formed in the structure
Specifying this system?
We issue technical submittals, U-value calculations, wind uplift calculations and detail drawings as part of the tender return.
Send us the specificationDelivered
All case studiesProjects using this system
EducationCommon questions
Hot Melt, answered
Why specify hot melt over a sheet system on a podium?
Because it is fully bonded. Under a loaded podium, a leak in a loose-laid sheet can travel a long way from the defect, which makes it practically unfindable. A bonded membrane keeps the defect and the leak in the same place.
Do you integrity test the installation?
Yes, as standard, and we invite the main contractor or client representative to witness it. You receive the test record before any protection or landscaping is loaded over the membrane.
Tender & project enquiries
Have a project for us?
Send Absolute Waterproofing your roofing enquiry or tender. Drawings, specifications and a link to the tender information can all go with it, and our estimating team will come back to you with a considered price rather than a holding email.
