Replacing your windows makes your home more comfortable, lowers your bills and, depending on your circumstances, lets you deduct part of the cost from your tax or apply for grants. Here is what is available today and how we handle it for you.
In many older homes, the windows are where most energy escapes. Replacing them with PVC or thermally broken aluminium windows and good glazing makes a difference from day one: less cold in winter, less heat in summer and less noise.
Grants change every year, so here we only include what we have checked in official sources or the specialist press. Last reviewed: 15 October 2026.
Royal Decree-Law (Real Decreto-ley) 7/2026 of 20 March extends, until 31 December 2026, the tax deductions for work on your home that reduces heating and cooling demand or the consumption of non-renewable primary energy. For work on entire residential buildings, they are extended until 31 December 2027.
Under the rules for these deductions, you can deduct 20% or 40% of the amount invested in the home, up to maximum limits, depending on the improvement achieved. This is proven with an energy performance certificate issued before and after the work. The property must be your main home or be rented out. Check your own case with your tax adviser.
The Agencia Andaluza de la Energía has announced incentives for the residential sector (resolution published in the BOJA, the Andalusian official gazette, on 25 September 2026). According to the published information, applications open on 22 October 2026 and the application period runs until 30 September 2027 or until the funds run out. It covers improvements to the building's thermal envelope, requires the energy rating to go up by at least one letter and sets a minimum investment. You need to check the official terms of the call (bases) to confirm whether your window project qualifies.
The Junta de Andalucía (regional government) scheme for improving the energy efficiency of homes has been closed to applications since December 2024, and the work had to be completed before 30 June 2026. It is not accepting new applications.
Approved in April 2026, it includes renovation and energy-efficiency schemes run by the regional governments (comunidades autónomas). At the time of this review we have not found an open Andalusian call for applications covering windows under this plan. We will update this information when one is published.
PVC: excellent thermal and sound insulation, maintenance-free and resistant to salt air. We work with Finstral systems.
Aluminium with a thermal break (known in Spain as RPT): slimmer frames, plenty of light and a wide range of colours. We work with Strugal systems.
Glazing: double glazing with an insulating air gap, low-emissivity (low-E) glass to reduce heat loss, solar-control glass on south- and west-facing windows, and acoustic or safety laminated glass where needed. The right combination depends on which way your windows face and how noisy your street is.
We take care of the process so you don't waste time on paperwork. We check which grant or tax deduction may suit your case, prepare the technical documentation for the windows and arrange the energy performance certificates with a qualified technician.
Important: some grants do not accept work that started before you applied. We check this before you sign.
Ask for your free grant assessment by WhatsApp on 665 26 11 55 or by email at info@kristall.es.
As of 15 October 2026, the income tax (IRPF) deduction for energy-efficiency work is available until 31 December 2026, and there is a new call for incentives from the Agencia Andaluza de la Energía (Andalusian Energy Agency), with applications from 22 October 2026. The Plan Eco Vivienda housing scheme is closed.
20% or 40% of the investment, up to maximum annual limits, depending on how much the home's energy efficiency improves. You need an energy performance certificate before and after the work, and the property must be your main home or be rented out.
Both work well by the sea if they are good quality. PVC insulates slightly better and is unaffected by salt air; thermally broken aluminium offers slimmer frames and more colours. We'll advise you based on your home.
Yes, we take care of the process: we advise you on the grants currently available, prepare the technical documentation and arrange the energy performance certificates.
We reply within 24 working hours. Free site visit and measuring anywhere in the province of Cádiz.
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