Purenite boxes

What is a purenite socket box

Purenite soffit box is a building insulation element that creates a space for shading technology, insulates the lintel and connecting joint, and creates neat construction details in one installation step.

Ideal technical solution
Quick and easy installation
Excellent insulation properties

I am interested in purenite boxes

Purenite boxes are one of the most effective undermount systems for installing exterior blinds. Their installation is very quick and simple, and with the right instructions, even a layman can do it. They are installed either in prepared pockets in the lintel area or above the window in the contact insulation.

Which purenite box do you want?

Basic purenite box variants:

PB

PB - a U-shaped box formed by purenite. It is mainly used where the insulation of the lintel is resolved. At KZS we still create a space for exterior louvres from a material that works with it.

PBI

PBI - purenite box with insulation. Can be in widths of 20-60mm. The most used and effective version.

PBL

PBL - an L-shaped box formed by purenite. It has similar specifications to PB with the that it takes up even less space in the KZS.

Types of purenite boxes

Boxes are manufactured in the type ranges shown or based on the requirements and needs of the building. We manufacture corner assemblies, assemblies for strip windows, boxes for canted windows, arches etc. However, the basis should be a drawing of the product or at least a site survey.

The insulation of the back of the boxes is supplied as standard in 20-60mm widths of PIR board. If necessary, we can combine different insulation thicknesses and equip the box with atypical insulation. Of course, we can also adapt the U-profile associated with the insulation. It is normally supplied powder-coated in standard RAL colours, but can also be painted in structural colours and renoliths.

What does a purenite box consist of?

The purenite box consists of two basic materials. The first is the Purenit structural board (3), which forms the front of the box (after treatment with a contact bridge it can be stretched across the facade), the ceiling and the sides. Purenit in the façade is virtually moisture-proof, non-dilating and non-reactive to construction chemicals. In addition, we can freely anchor brackets or blind holders into it as a structural board.

The second part of the box is the insulation. This forms the back of the box, which adheres to the lintel, the connecting joint and the window frame. As an insulator we use PUREN MV (4) PIR insulation board.

Mounting U profile (1) is not only one of the supporting elements of the box, but also forms a functional and aesthetic detail of the connection of the box insulation to the window frame.

Substitute bar (2) is located on the front of the box. Different depths allow for the application of additional insulation or final cladding. As standard it is set in raw aluminium for better embedding in the façade. It can also be painted.

*Purenite and PIR insulation board datasheets can be found in appendix 1 and 2 at the end of this document
** The details, images and 3D models shown are illustrative and may not suit your project. Consult your facade system supplier for the location and method of incorporating the PURbox into the ETICS system.

PIR insulation for PBI

PIR insulation thickness	20mm	30mm	40mm	50mm	60mm
Heat transfer coefficient U	1.1	0.76	0.6	0.49	0.41
R thermal resistance	0.7	1.1	1.45	1.85	2.2

The dimensions shown are the standard dimensions offered. On request we can offer dimensions 70 - 200 mm.

Why use purenite socket boxes on site?

IDEAL BUILDING DETAIL SOLUTION

boxes are strong and self-supporting
due to the insulating properties of Purenit and PIR insulation, they eliminate thermal bridging
Can be combined with all façade systems (contact insulation, ventilated façades and brick, stone and wood cladding).
Aesthetic detailing between window and box insulation

Simple installation in one step

installation is simple and quick - even facade installers can do it
boxes and lining do not need to be oriented - just include the production dimensions of the windows in the order
the whole system is variable and can be easily adapted to the site conditions
fast delivery time

NATURAL FEATURES

boxes are moisture and construction chemical resistant in the façade
show exceptional dimensional stability
have class B fire resistance (they do not drip in case of fire, only charring)
are exceptional in strength and light weight
their insulation properties also meet the parameters of passive buildings

VARIABLE SYSTEM

purenite boxes can be supplemented with different thicknesses of PIR insulation according to the needs and possibilities of the building
the system can be supplemented with different types of lining and sub-parapet bed
option to choose the internal coating of the box
fast delivery time
base profile in all RAL shades, structural colours and basic renolit foils
variable choice of the depth of the locking rail and the possibility of painting it
atypical boxes (angles, curves, etc.)

Downloads

Instructions for measuring and installation

Installation instructions PURbox and prefabricated lining

Installation conditions 2026