As energy bills rise, “how much does external insulation cost?” appears on every building meeting agenda. The price varies considerably from building to building, because the cost is not one item but a chain running from facade area to scaffolding duration. This article opens up that chain so you can read quotes properly.
The factors behind the cost
- Facade area (m²): the main multiplier. Window openings are deducted, but sills and edge details add labour.
- Board type: EPS is economical and widely used; XPS at the plinth and in damp-exposed zones; mineral wool on tall buildings where fire safety is required, at a higher price. For comparison see external and waterproof insulation.
- Board thickness: greater thickness costs more in material but lowers heating and cooling bills. Thickness is recommended according to climate and the building’s condition.
- Scaffolding: erection, hire duration and safety measures; its share grows with building height.
- Top coat: mineral plaster offers texture and durability; exterior paint is more economical. Colour and texture choice affects price.
- Condition of the existing facade: crack repair, removing blistered render, stripping old cladding — surface preparation is the underrated item that explains the difference between quotes.
- Detail density: balconies, sills, movement joints and decorative profiles all increase labour compared with a plain facade.
The logic of cost per flat
Insulation is applied to the building; the bill is divided among the flats. It is normal for the share per flat to differ between two buildings on the same street:
| Factor | Lowers the share per flat | Raises it |
|---|---|---|
| Number of storeys | Many storeys (area per flat falls) | Few storeys, house-like |
| Facade geometry | Plain, flat facade | Recessed and projecting facade |
| Window ratio | High | Low |
| Facade condition | Sound surface | Surface needing repair |
How long before insulation pays for itself?
The saving depends on the building’s previous condition, the thickness chosen and the climate. Because a significant share of heat loss occurs through external walls, properly applied insulation permanently reduces heating and cooling costs; the payback period varies with energy prices. Treat quotes promising a specific number of years with caution.
What to check in a quote
- Are the board type, brand and thickness stated?
- Are the number of fixings, mesh and adhesive included?
- Are scaffolding and safety measures included in the price?
- Does surface preparation (stripping, crack repair) appear as a separate line?
- Are the top coat type and colour choice settled?
- Are details such as sills and reveals within scope?
Comparing prices without equalising scope is misleading; the lowest quote is usually low because something is missing. For general criteria see choosing a renovation company.
How the process works in an apartment building
Owners’ meeting decision → facade measurement and consultation → itemised quote → contract and work schedule → scaffolding → application → inspection and handover. For coordination with management and informing neighbours, see renovating in an apartment building.
Demgirişim carries out measurement, material selection and application for thermal and waterproof insulation with a single team, and manages coordination with building management on apartment projects. Consultation and written quote are free within Istanbul.
Frequently asked questions
How is external insulation cost divided per flat?
The total based on facade area is usually shared among owners by land share or equally. In buildings with a wide facade and few storeys the share per flat rises; in taller buildings it falls.
Which insulation board is more economical?
EPS is the most common and economical option; mineral wool is chosen where fire performance is required and costs more. Greater thickness raises the material cost but also increases energy savings.
When is the insulation price fixed?
After facade measurement and a site consultation. Figures given without seeing the condition of the facade, building height and detail count are not binding.
The initial consultation and written quote for Thermal & Waterproofing are free within Istanbul. Scope, duration and cost are confirmed after the consultation.