ROCKCLOSE ®

Minimises thermal bridging at door and window

reveals in cavity wall constructions
 ROCKCLOSE®

ROCKCLOSE®
ROCKCLOSE® is an insulated damp
proof course, developed to minimise
thermal bridging at door and window
reveals in masonry cavity walls.
The product consists of a strip of
semi-rigid non-combustible stone
wool insulation, bonded to a black
polyethylene DPC. Installed as work
proceeds between the outer masonry
leaf and internal closer block prior to the
frames being fitted.

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Advantages
• Minimises thermal bridging around openings

• Integral damp proof course

• One-hour fire integrity and 30 minutes

insulation

• One width covers most applications

• Self-supporting and easy to handle

• Simple to install

Description Applications
ROCKCLOSE® is an insulated cavity ROCKCLOSE® has been specifically
closer. The product is designed to developed to minimise thermal bridging
minimise thermal bridging around at door and window reveals whilst also
windows and doors in first-fix cavity providing a fire-resistant cavity closer.
wall installations with a returning inside
leaf. Designed to be installed as work The effect of thermal bridging has
proceeds between the outer masonry been a long-recognised problem,
leaf and internal closer block prior to which has been given even greater
the frames being fitted. significance under the new Part L
Building Regulations. In a typical
The product consists of a strip of semi- building, as much as 20% heat loss can
rigid non-combustible ROCKWOOL occur around door and window reveals
insulation, bonded to a black if not correctly addressed. Building
polyethylene DPC. Regulations require that thermal bridges
that occur at junctions between building
elements are included in the calculation
of transmission heat losses.

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Performance
For masonry cavity walls, ROCKWOOL ROCKCLOSE® will exceed the minimum
thermal resistance path through the closer of not less than 0.45m2 K/W as required
under Accredited Construction Details (see table below).

Thickness Thermal resistance

(mm) (W/m2K)
20 0.570
30 0.857
50 1.430

Returning blockwork

ROCKCLOSE Insulated DPC

Dimensions

Insulation DPC
Thickness Width Length Length Width Bottom lap
20, 30 & 50mm 100mm 1200mm 1300mm 180mm 100mm
(40mm lap each side
of the insulation)

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Installation
ROCKWOOL ROCKCLOSE® is suitable for vertical and horizontal applications and
is designed to be installed as work proceeds, between the outer masonry leaf and
closing inner leaf prior to fitting of window and door frames. The product can be
easily cut on site as required, but always ensure the 100mm DPC lap is retained.

• Where more than one length is required, the adjoining lengths of insulation are
simply tightly butt jointed together

• The upper piece must be installed with the 100mm DPC overlap at the bottom,
dressed over the DPC face of the lower piece

• DPC side laps: The DPC overlaps the insulation by 40mm on each side. On the
cavity side, the DPC should extend into the cavity along the inside face of the
outer leaf. On the opening side, the DPC should be formed against the window/
door frame and sill in the traditional method

• Installation must follow normal good practice for the detailing of DPCs, as set
out in BS EN 1996-2: 2006, BS 8000-3: 2001 & BS 8215

Technical information
The following NBS clauses include ROCKCLOSE® F30 :18, F30:180.

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Sustainability Environment
As an environmentally conscious Made from a renewable and plentiful
company, ROCKWOOL promotes naturally occurring resource,
the sustainable production and use ROCKWOOL insulation saves fuel costs
of insulation and is committed to a and energy in use and relies on trapped
continuous process of environmental air for its thermal properties.
improvement.
ROCKWOOL insulation does not
All ROCKWOOL products provide contain (and has never contained) gases
outstanding thermal protection as well that have ozone depletion potential
as four added benefits: (ODP) or global warming potential
(GWP).

ROCKWOOL is approximately 97%

Fire resistance recyclable. For waste ROCKWOOL
material that may be generated
during installation or at end of life, we
Acoustic comfort are happy to discuss the individual
requirements of contractors and users
Sustainable materials considering returning these materials to
our factory for recycling.
Durability

Health & Safety

The safety of ROCKWOOL stone wool
is confirmed by current UK and Republic
of Ireland health & safety regulations
and EU directive 97/69/EC:ROCKWOOL
fibres are not classified as a possible
human carcinogen.

A Material Safety Data Sheet is

available and can be downloaded
from www.rockwool.co.uk to assist in
the preparation of risk assessments, as
required by the Control of Substances
Hazardous to Health Regulations
(COSHH).

Interested?
For further information, contact the Technical Solutions Team on 01656 868490
or email technical.solutions@rockwool.co.uk
Visit www.rockwool.co.uk to view our complete range of products and services.
Copyright ROCKWOOL September 2018.

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The ROCKWOOL Trademark Disclaimer Photography and Illustrations

ROCKWOOL® - our trademark ROCKWOOL Limited reserves the right The product illustrations are the property
to alter or amend the specification of of ROCKWOOL ltd and have been
The ROCKWOOL trademark was
products without notice as our policy created for indicative purposes only.
initially registered in Denmark as a
is one of constant improvement. The
logo mark back in 1936. In 1937, it Unless indicated below, the photography
information contained in this brochure
was accompanied with a word mark and illustrations used in this guide are the
is believed to be correct at the date
registration; a registration which is now property of ROCKWOOL Limited. We
of publication. Whilst ROCKWOOL
extended to more than 60 countries reserve all rights to the usage of these
will endeavour to keep its publications
around the word. images.
up to date, readers will appreciate
The ROCKWOOL trademark is one of the that between publications there may If you require permission to use
largest assets in the ROCKWOOL Group, be pertinent changes in the law, or ROCKWOOL images, you must apply for
and thus well protected and defended by other developments affecting the a Usage Agreement. To apply, write to:
us throughout the world. accuracy of the information contained marketcom@rockwool.com.
in this brochure. The applications
If you require permission to use the
referred to within the brochure do not
ROCKWOOL logo for your business,
necessarily represent an exhaustive list
advertising or promotion. You must apply
of applications. ROCKWOOL Limited
for a Trade Mark Usage Agreement. To
does not accept responsibility for the
apply, write to:
consequences of using ROCKWOOL
marketcom@rockwool.com.
in applications different from those
described within this brochure. Expert
Trademarks advice should be sought where such
different applications are contemplated,
The following are registered trademarks
or where the extent of any listed
of the ROCKWOOL Group:
application is in doubt.
ROCKWOOL®
© ROCKWOOL 2018. All rights reserved.
ROCKCLOSE ®

RAINSCREEN DUO SLAB®

HARDROCK®
ROCKFLOOR®
FLEXI®
BEAMCLAD®
FIREPRO®

ROCKWOOL Ltd
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September 2018

ROCKWOOL Limited
Pencoed
Bridgend
CF35 6NY
Tel: 01656 862 621
info@rockwool.co.uk
rockwool.co.uk