Wall cavity inspection
We assess the cavity width, debris, signs of damp and existing insulation before making a recommendation.
- Technical inspection
- The right choice of materials
- Clear quotation
Warm walls without major renovation work
Cavity wall insulation with a subsidy
Have your wall cavity checked for suitability and find out which subsidy may be available. Installation is usually quick and makes your home more comfortable straight away.
- Preliminary inspection of the wall cavity and external wall
- Quick completion with minimal disruption
- Subsidy application support from start to finish
Free advice on cavity wall insulation
Have your external walls assessed and find out which subsidy may be available for your home.
10 years warranty
We handle the subsidy
Expert installation
Rated 5 stars
Subsidies clearly explained
ISDE for cavity wall insulation
Cavity wall insulation involves filling the space between the inner and outer walls with insulating material. Subsidy eligibility depends on conditions including the surface area and insulation value.
We inspect the wall cavity, brick pointing and external wall beforehand. This prevents insulation from being installed in an unsuitable wall and ensures an accurate quote.
Check my optionsSuited to your home
A comprehensive approach to your façade
Good cavity wall insulation starts with a sound, suitable external wall.
Fill the wall cavity
The insulation material is distributed evenly throughout the wall cavity through small drilled holes.
- Minimal disruption
- Quick completion
- Drill holes neatly filled
Check the brick pointing
Damaged brick pointing can let moisture in and is therefore taken into account in the assessment.
- Healthy external walls
- Better protection
- A neat finish
How does this step benefit you?
Warmer interior walls
Walls feel less cold and rooms stay more comfortable.
Fewer draughts
Cold draughts along external walls are reduced.
Quick completion
The work can often be completed within one working day.
Minimal disruption
The material is blown in from the outside.
Lower heating demand
Your home retains the heat generated more effectively.
Subsidy application support
We help gather the correct information for the application.
Explore more options
Create a comprehensive plan for your home
Combine measures where it makes technical and financial sense.
From advice to subsidy application
- 1
Personal advice
We discuss your home, your requirements and which measure may be suitable.
- 2
Inspection and quotation
A specialist assesses the situation and prepares a clear, tailored quotation.
- 3
Check subsidy eligibility
We check which national and municipal schemes may apply.
- 4
Expert installation
Our installers carry out the work neatly and record the required details.
- 5
Complete your application
Once the work is complete, we help with the supporting documents for your subsidy application.
How do cavity wall insulation grants work?
Cavity wall insulation is eligible for the Dutch government's national ISDE grant. You receive a fixed amount per square metre insulated. If you have two or more insulation measures installed within two years, such as cavity wall and roof insulation, the amount per square metre doubles.
Many local authorities also offer their own insulation grants, which can often be combined with ISDE. You'll find the current conditions for each local authority on our local grant pages.
ISDE grant eligibility criteria
ISDE requirements include a minimum area to be insulated and a minimum thermal performance for the material. The work must be carried out by a qualified company, and you apply for the grant using the invoice, proof of payment and installation details. The exact conditions may change each year; we check them for you.
- You own and live in the property.
- The insulation is installed in an existing home.
- The material meets the required thermal performance standard.
- The work is professionally carried out and documented.
Is your home suitable for cavity wall insulation?
Most homes built between around 1920 and 1975 have cavity walls with little or no insulation. During an inspection, we measure the cavity width, check for debris and moisture, and assess the condition of the pointing. We only recommend insulation if the external walls are suitable.
Which insulation material is used?
We insulate the cavity with glass wool. The glass wool is blown in through small drill holes and fills the cavity evenly. The holes are then neatly sealed in the colour of the pointing.
Combine measures for a larger grant
Cavity wall insulation works well alongside roof insulation, floor insulation, crawl space ground insulation and energy-efficient glazing. Combining two or more measures reduces heat loss even further and doubles the ISDE grant per square metre.
Frequently asked questions
How much grant funding can I get for cavity wall insulation?
The ISDE grant pays a fixed amount per square metre insulated. If you combine two or more measures within two years, that amount doubles. A local authority scheme may also be available. We calculate how much you could receive for your home.
When should I apply for the grant?
You apply for an ISDE insulation grant after the work has been completed, using the invoice and proof of payment. Some local authority schemes require you to apply in advance. We'll explain which steps to take and when.
Can I combine ISDE with a local authority grant?
In many areas, yes. Conditions vary between local authorities, so we check this for your specific address.
How long does cavity wall insulation take?
For an average home, cavity wall insulation is often completed within one working day. No building work is needed inside, as the material is blown in from outside.
Does Greenisolatie help with grant applications?
Yes. We check which schemes are available for your home, record the required installation details and help with your application.
How much does cavity wall insulation cost?
The cost depends on the area of the external walls and the condition of the cavity. Request a free quote for a tailored proposal.
What our customers say
EXCELLENT
Based on 161 reviews on Google
Super fijn bedrijf! Snel geholpen, netjes gewerkt en duidelijke uitleg over de subsidie. Echt een aanrader.
Mandy
Posted on Google
Prettig contact van begin tot eind. De monteurs waren vriendelijk en lieten alles schoon achter.
Inge Slinger
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Goede en heldere communicatie, afspraken worden nagekomen en het werk is netjes uitgevoerd.
A.
Posted on Google
Binnen één dag geïsoleerd. Het huis voelt direct warmer aan en de stookkosten zijn merkbaar lager.
Alisia
Posted on Google
Vakkundig team dat goed uitlegt wat er gebeurt. Zeer tevreden over het eindresultaat.
Peter Stavenuiter
Posted on Google
Van offerte tot uitvoering alles perfect geregeld, inclusief hulp bij het aanvragen van de subsidie.
Danielle Thijssen
Posted on Google
25.000+ people have already chosen us!