Replacing roof windows vs thermal upgrading the attic - a comprehensive guide
Roof and loft renovations associated with thermal modernisation should include the replacement of roof windows. This is an essential step for maintaining maximum energy efficiency of the entire building.
Roof windows installed decades ago were not subject to today's stringent building standards. Over the years, production technology has undergone enormous development, and the main focus has become on retaining heat inside the home. For this reason, when planning a loft renovation, it is essential to consider replacing the joinery. Experts assume that replacement of roof windows should occur on average once every 20 years.
Energy efficiency - the key parameter of modern windows
When choosing a good quality roof window, focus on its thermal insulation performance. The most important factor is the heat transfer coefficient (Uw) - the lower it is, the better the insulation. Building regulations currently require this coefficient not to exceed 1.1 W/m²K. However, there are models on the market that significantly exceed these requirements.
It is estimated that heat loss through old window frames can be as high as 15% to 30%. Choosing the right windows is therefore crucial for:
Reducing heat loss in winter.
Energy optimisation and reducing heating bills.
Wise use of natural resources.
Which energy-efficient windows to choose? OKPOL brand solutions
The Polish company OKPOL offers modern, 3-pane roof window models. They are equipped with two inter-pane frames, a safe handle with a key and a ventilator, which ensures a constant flow of fresh air without creating draughts. The low-e coatings used effectively protect against heat loss in winter and against overheating of the loft in summer.
The most popular OKPOL energy-saving models:
** Wooden windows (ISOV I22)** - the heat transfer coefficient is Uw = 1.06 W/m²K.
Multichamber PVC windows (IGOV N22) - the heat transfer coefficient is only Uw = 0.83 W/m²K.
Are roof windows environmentally friendly?
Yes, modern production takes care of the environment. OKPOL wooden windows with SuperTermo technology are made of glued pine wood from sustainable sources (confirmed by FSC certificate). Knots are cut out, which increases the durability and safety of the profiles. The company also has a zero waste policy - wood waste is processed into pellets to heat the factory, and the PVC profiles are 100% recyclable for future use.
Roof window replacement - size, material and features
1. Size selection and attic lighting
Proper natural light illumination is the basis for comfort. According to building standards, the ratio of glazing size to floor area in living spaces should be 1 window per 8 m² of floor. Often builders opt for a 1:1 ratio (new window to replace old). However, if more light is desired, it is worth considering inserting additional windows or combining them into composite sets.
2. Wood or PVC?
The choice of profile material depends mainly on the purpose of the room:
PVC windows: Ideal for rooms with high humidity (kitchens, bathrooms, attic laundry rooms).
Wooden windows: Ideal for use and presentation in bedrooms, living rooms and children's rooms.
3. Method of opening and electric windows
Standard windows rotate 180 degrees. However, you will also find in the OKPOL range:
** Tilt and slide windows:** An innovative solution that does not take up space inside the room. The sash opens up to 62° and the sliding function allows the outer pane to be turned inwards for easy cleaning.
Remote-controlled windows (ISC and IGCV): An excellent choice for high-set windows.
They have the same great performance, and can be controlled from the seat with the remote control.
Roof window accessories - protection from the sun and noise
Window accessories not only add variety to a space, they also have important insulating functions:
Exterior awnings: They reflect the sun's rays before they reach the glass, preventing the loft from heating up without obstructing the view.
External blinds: They provide complete shading and reduce noise from outside.
Internal roller blinds and pleats: Aesthetic barrier to the sun, available in a wide range of colours and materials (full range available in "Accessories for roof windows" OKPOL catalogue).
Safe and professional installation
Window replacement does not have to mean troublesome demolition of walls or disturbing the roof structure. If you keep the same size joinery, the installation takes place in the same place. For better aesthetics, you may decide to replace the entire window recess (stile).
Important: The installation of roof windows should always be carried out by specialised professionals - decontractors. A badly installed window can ruin the energy balance of the building and damage the roof trusses.
OKPOL Technical Support
Facade windows are easier to install, whereas installing roof windows requires expert knowledge and strict adherence to instructions. This is why the OKPOL brand has launched a special Technical Assistance Department. Investors can benefit from the support of Technical and Sales Advisors at every stage - from model selection to final installation.
All technical parameters and available models can be found in the clear Catalogue of windows and roof hatches on the manufacturer's website (www.okpol.pl).