ᐅ Energy-Efficient Home Renovation: Is Involving an Architect Beneficial?

Hello everyone,

We want to carry out an energy retrofit on a house from the 1970s. The house is in its original condition. It has a full floor, a basement, and a converted attic. The living area is approximately 180 m2 (1,940 sq ft). The basement adds another 120 m2 (1,290 sq ft). Part of the basement is planned to be converted into a separate apartment (some rooms are already partially finished for residential use).

We aim to renovate to KfW 70 EE standard (KfW 261) and already have a preliminary approval certificate. For the separate apartment, we need a building permit / planning permission. We want to make only minor changes to the floor plan. We do not require an architect for the interior work.

I have read the building guide from ant11, which focuses specifically on new construction. Naturally, the simplest approach would be to commission all phases of service from an architect. I have contacted one architect regarding this (I understand more should be contacted for quotes), and their fee was quoted at €60,000. I find this extremely expensive. Therefore, I wonder if it is worth the cost?

In which areas is it essential to hire an architect, and why? Where could you potentially save that expense? What would be a good value-for-money solution?

This is about the energy-related measures: window replacement, roof insulation, facade insulation, basement floor insulation, and perimeter insulation.

It is very important for us to have expert supervision on site to ensure the work is carried out correctly. We are not able to assess this ourselves. But does this necessarily have to be an architect?

What is your general recommendation for renovations?

I am sure some details are missing that I haven’t considered. Just let me know, and I will provide them.

Thank you for your responses.

ChriLenaMZ schrieb:

This concerns energy-related measures: window replacement, roof, facade, basement floor, and perimeter insulation.

It is very important for us to have on-site expertise—that is, an expert who oversees that the work is carried out correctly.

Have the energy consultant collaborate on the project. They specify exactly what needs to be done. For construction supervision, you should find a certified surveyor or inspector. These professionals are widely available—through organizations like the Homeowners’ Association or similar.

For a standard energy retrofit, an architect is not necessary.

I think that’s completely over the top.

I would calculate everything myself (U-values, dew points, thermal bridges…) and plan it out. Get approval from the energy consultant before implementation and sort out the rest with the contractors.

I wouldn’t involve an architect, only if structural calculations are relevant would I seek advice.

If you don’t want to deal with it yourself, go with an architect and let them handle the planning and site supervision. It will just be very expensive.

However, for the building permit / planning permission application, a licensed professional, such as an architect, is required.

ChriLenaMZ schrieb:

The basement is partly going to be converted into a granny flat / accessory dwelling unit (some rooms are already partially finished for residential use).

This sounds like the basement rooms are heated but not officially recognized as living spaces. -> Architect.

Thank you for the many responses. The overall consensus is quite clear. Our energy consultant is an architect. Accordingly, the energy performance certificate for KfW 261 cost a considerable amount (mid four-figure sum). Perhaps this is typical for the market, but I was still surprised (okay, you would get back half of it as a repayment grant). We definitely need it for the granny flat, yes. Because it is currently not classified as living space, although it is heated. To make things more complicated, the ceiling height is also a few centimeters (centimeters) short. Therefore, we definitely need a building permit/planning permission and an architect for converting it into living space.

ChriLenaMZ schrieb:

Because this area is not currently considered living space, although it is heated. To complicate matters, it also lacks a few centimeters (inches) of ceiling height.

This could be the deal-breaker for a granny flat / accessory dwelling unit or living rooms!