Complete guide: terrace waterproofing in Paris

What is terrace waterproofing?

Terrace waterproofing is a technical protection system consisting of applying an impermeable membrane (bitumen, resin, PVC, or EPDM) designed to prevent any water infiltration into the building structure. A high-performance waterproofing system protects the structural framework and prevents water damage.

Why is terrace waterproofing crucial in Paris?

Parisian terraces are subject to varied climatic conditions: heavy rain, winter frost, summer heat. Failing waterproofing can lead to costly infiltration into habitable areas. Here's everything you need to know to choose the right waterproofing system.

The 4 main waterproofing systems

1. Bituminous membrane

The most common system in France. Bituminous membranes (SBS or APP) are torch-welded or self-adhesive. They offer excellent resistance to UV and thermal bridges.

2. Liquid waterproofing resin (SEL)

Ideal for complex surfaces with many upstands, penetrations or angles. The resin cross-links in place forming a continuous jointless membrane. Particularly suited to Parisian balconies.

3. PVC membrane

Heat-welded synthetic membrane, resistant to UV and chemical agents. Ideal for large surfaces. Easily repairable if punctured.

4. EPDM membrane

Very flexible synthetic rubber with excellent ageing and thermal variation resistance. Lifespan 30-50 years. Ideal for green roofs.

Waterproofing systems comparison table

System	Indicative price/m²	Lifespan	Balcony suitable	Large surface suitable
Bitumen	€40-80	15-20 years	✓	✓✓
Liquid resin	€60-120	20-25 years	✓✓	✓
PVC	€50-100	20-30 years	✓	✓✓
EPDM	€60-120	30-50 years	✓	✓✓

The steps of a waterproofing intervention

A professional waterproofing intervention takes place in 5 key steps:

1. Diagnosis: visual inspection and substrate permeability test
2. Preparation: cleaning, drying and levelling of the substrate
3. Primer: application of a bonding primer
4. Waterproofing: installation of the chosen system with upstands on singular points
5. Protection: installation of heavy protection (slabs, gravel) or light (paint)

FDM ENERGIE provides a complete free diagnosis of your terrace. Contact us for a personalised quote based on your surface and constraints.