Where does our information come from?
We look for models, prices and specifications on manufacturers’ websites, in price lists and in technical documents. Where available, our reviews also draw on consultations and checks. We have not assessed every manufacturer to the same extent.
We distinguish reviews selected by manufacturers from experiences shared on independent websites and forums. One complaint or positive comment does not represent every customer’s experience. For legal questions, we consult official sources.
How do we compare prices?
The catalogue shows the price and specification of a particular model. In our price comparison, we estimate the cost of a fully finished house with foundations, an air-to-air heat pump and heat recovery ventilation. We use building footprint and a consistent VAT basis.
When a manufacturer publishes a price for an extra, we use it. Otherwise, we add the assumption stated in our calculation. The result is our estimate for budget planning. The full calculation, assumptions and sources are shown alongside the price table.
What do the stars and rankings mean?
The stars are our editorial assessment, rather than an average of customer reviews. We assess four things:
- Price: the cost and what the buyer receives for that amount.
- Quality: construction, materials, technical information, warranty and findings from checks.
- Speed: production and construction timelines. Production, waiting for a slot and installation are separate stages.
- Reviews: available customer accounts and the cooperation they describe.
The ranking is an editorial choice. It is not a mathematical total of the four scores: we also consider layout changes, the range of services and how convenient the process is for the buyer.
Which manufacturers do we compare?
How do we update the information?
We change a source-check date only after checking the source. A calculation may be updated on a different day, so we show that separately on the price page. If a manufacturer is unclear about VAT or the type of floor area, we explain the assumption in our methodology.
Spotted an error or have a newer specification? Email [email protected] and include a link to the relevant page or document.