Windows + Doors: Retrofit
Why it Matters. How we do it.
At Stoic Homes, we approach retrofit with discipline, clarity, and focus.
Every element must contribute to performance - windows and doors included.
While often seen as a cosmetic upgrade, poorly performing glazing and badly installed doors are weak points in the building envelope. They allow heat to escape, cold to creep in, and energy bills to rise. That's not just inefficient - it's avoidable.
We treat windows and doors as part of the overall strategy: not in isolation, but as essential components in achieving real, measurable outcomes in energy performance, comfort, and carbon reduction.
Why Windows and Doors Matter in Retrofit
Most existing homes were built before energy performance was a consideration.
Draughts, single glazing, and poorly sealed frames are common. Left unaddressed, these areas can account for over 25% of heat loss in a home.
In a low-carbon retrofit, everything is connected. You can install all the insulation you like, but if your windows leak air or your doors let in the cold, the system fails.
What We Focus On
1. Performance, Not Appearances
We specify based on U-values, air permeability, and frame construction, not brochure images. Most of our retrofit projects use triple-glazed units with airtight timber or timber-aluminium composite frames, all installed to high airtightness standards.
Every product is chosen for a reason, backed by data.
2. Installation is Critical
A high-performance window installed poorly is a liability. We only use trained teams who understand building physics, thermal bridging, and airtightness detailing.
We ensure airtight membranes, sealing tapes, and expansion foams are applied correctly - because detail matters.
3. The Right Material for the Right Job
We lean toward FSC-certified timber and low-carbon materials where practical. Every product must meet our thresholds for durability, sustainability, and performance. We avoid uPVC wherever possible due to its lifecycle impact.
4. Understanding Context
We work with what's already there. In retrofit, that often means navigating awkward reveals, limited openings, or heritage restrictions. Where necessary, we integrate secondary glazing, vacuum units, or bespoke solutions to balance performance with planning constraints.
5. A System, Not a Surface Fix
Windows and doors don't sit in isolation. We look at:
Solar orientation - for passive gains
Thermal bridging at reveals and sills
Ventilation strategy - to prevent condensation and maintain indoor air quality
Airtightness testing - to verify performance Everything is part of the wider fabric strategy.
What to Expect from Stoic Homes
We approach every project with the same mindset:
Do what works. Leave out what doesn't. Build for the long term.
That means no trends, no guesswork, and no greenwash. Just results. If you're serious about reducing your home's energy use, improving comfort, and making long-term improvements with integrity - we're ready to help.
FAQ’s
-
Thermal bridging occurs when heat escapes through elements of a building that are more conductive than surrounding insulation. In retrofits, poorly insulated window frames or junctions can become major thermal bridges. High-performance windows are designed to minimize this by using thermally broken frames and well-insulated materials that reduce heat loss and prevent cold spots.
-
Triple glazing significantly improves thermal insulation and acoustic comfort. It adds a third pane of glass with an additional gas-filled cavity, reducing heat loss and external noise. For deep retrofits or EnerPHit-level performance, triple glazing helps meet airtightness and thermal performance targets.
-
A rebate is the area where the sash (opening part) meets the frame. High-quality rebates help form tight seals that block air leakage and moisture ingress. In retrofits, well-designed window systems with multiple sealing layers are essential for maintaining airtightness and weather resistance.
-
Airtight windows reduce drafts, prevent moisture ingress, and improve energy efficiency. Achieving high airtightness depends on both the quality of the window design (including seals and profiles) and the care taken during installation. Even small gaps can drastically reduce performance in low-energy buildings.
-
Even the best-performing windows will under-deliver if not installed correctly. Precise installation ensures airtight connections with the building fabric, maintains insulation continuity, and prevents water ingress. In retrofits aiming for EnerPHit or similar standards, poor installation can undermine the entire envelope strategy.
Free Consultation.
Pick a date and time for a free initial consultation using our Calendly app.