Plus Points that offer real value

A top performer – down to 5° pitch

Lacker's topSwing roof windows offer a delicately crafted, architecturally appealing, premium-quality daylighting and ventilation solution for attic conversions. topSwing is suitable for roof pitches down to 5°.

The sky's the limit

 The potential applications are virtually unlimited.

  • Attic conversions in listed buildings
  • Roofs in residential new-builds
  • Conservatories
  • Sawtooth roofs
  • Stick-system assemblies


Ready-assembled delivery

To allow prompt and trouble-free installation, we supply the windows as fully pre-assembled units complete with glazing. This allows straightforward fitting of the roof windows – in much the same way as fixed lights – with no time lost through fine adjustment of hardware etc.

Top glazing solutions

Our topSwing roof windows are manufactured, to your specifications, with

  • Single glazing
  • Double glazing
  • Triple glazing
  • Solar-control glazing
  • Screenprinting

Bespoke products made to fit

The size of our topSwing roof windows is adapted in line with project-specific requirements regarding the place of installation.

Standalone solution 

As single units, our window systems are manufactured in widths of up to 1,000 mm and heights of up to 2,000 mm. The exact sizes depend on the width-to-height ratio of the unit.

Multi-part solution

Alternatively, multi-part topSwing assemblies are also manufactured in widths of up to 6,000 mm for strip windows. 

Made-to-measure advice

We should be glad to counsel you on the optimum window sizes for your particular scheme. With all due regard, of course, to your specific requirements and preferences. After all, our ultimate goal is to find the most economical solution for you and your project. 

A high profile

For our frames, we exclusively use highly insulating, thermally broken multi-chambered sections with 24 mm adapter thickness. The sections can be adjusted to fit all standard stick-system assemblies, steel sections and timberwork structures. Packing for greater adapter thicknesses and the widening of the adapter edge are feasible.

All colours of the rainbow

The frame sections are only visible from the inside and can be anodized or coated in any required RAL or DB colour.

Durably weathertight

All weatherstripping is made from ageing- and weather-resistant silicone or EPDM, with double-blade seal. The weatherstripping materials and design guarantee full and reliable weather exclusion even after years of service.

Driven by ingenuity

Innovative (230 V and 24 V) chain motors are used for our topSwing windows. An intelligent synchronization control is additionally fitted for windows with two or more drives.

Keeping a watchful eye

If necessary, the roof window's current (open/closed) position status can be monitored using reed switches or an incremental encoder system.

Connections included

The wiring is integrated in the window and carried within the assembly to a single connection point.

Cables made to measure

As an optional extra, we supply our windows complete with cabling. Cable lengths vary from window to window and are adapted by us to meet project-specific requirements.

Certified excellence

In all tests conducted by independent institutes, our topSwing roof windows exclusively deliver top results: We should be glad to send you the very latest test results for driving rain resistance to DIN EN 12208 and air permeability to DIN EN 12207.

Simply send us an e-mail.

U value upon request

Thermal resistance is largely dictated by window size. Where suitably sized and optimally glazed, our roof units – with a thermal transmittance (U value) of up to 1.2 W/(m2K) – offer exceptional cost and energy efficiency performance. We should be glad to calculate the value for your own window sizes and glazing requirements. Simply send us an e-mail.

Optional extras

Position status monitoring

The (open/closed) position status of topSwing roof units can be monitored using reed switches or an incremental encoder system. 


Stainless-steel frame for tile roof applications

For good-practice and thermally efficient installation of our window systems in tile roofs, we supply our products with stainless-steel frames upon request.   


Insect/bird screens and sunshades

All topSwing roof windows can be retrofitted with bird and insect screen systems or sunshades. These are simply fixed to the frame in the interior.  

Lifting lugs for crane assembly

We also strive to make our window systems fast and easy to install. Our window units are therefore supplied with lifting lugs for crane assembly upon request.