weber.pral M is a one coat, ready mixed, cementitious, weather resistant, external decorative, through coloured render, suitable for most types of brick or blockwork. Factory produced from carefully selected raw materials for consistency of product, it only requires the addition of water on site. The through colour and one coat features allow fast application with shorter programme periods, thereby reducing associated scaffolding and site costs and permitting the completion of ground works at an earlier stage. weber.pral M has been awarded an A+ Green Guide Rating as defined in the BRE Global 2008 Green Guide to specification.
weber.pral M is available is a range of 24 colours. 6 standard colours and 18 special colours. Specifiers should consult the weber.pral M Colour Chart and, whenever possible, obtain samples prior to specification.
Scaffolding must be independently tied to allow for an uninterrupted application. Any faults in the structure, particularly those which may lead to moisture penetration must be rectified.
To avoid dampness and discolouration rendering should be avoided below DPC and within 150 mm of ground level.
All surfaces must be sound, clean, suitably dry and free of any material which may impair adhesion. The substrate should be suitable for rendering with a designation III mix (1:1:6).
Arrises and feature stops may be formed using clean straight timber battens.
Alternatively, suitable beads may be used but, with a scraped finish, these will be evident and must be accepted as a feature. Please note that scraped renders may, during the scraping process, tend to spall away from the nose of some angle beads. Refer to weber's Technical Department for advice on suitable profiles.
Mask as required. Edging tape must be removed before the material has dried.
Expansion joints should be included as required by the substrate and carried through all applied materials.
Do not apply to gypsum plaster or previously painted surfaces.
weber.pral M should be mixed with 5 - 5Â½ litres of clean water using either a suitable render spray machine, drill and whisk or tumble mixer.
To ensure colour consistency, the materials required for complete and adjoining panels should be of the same batch number or be thoroughly mixed together before use.y.
For best results, use as little water as possible and mix to give a workable consistency.
Note: weber.pral M may stiffen on standing. Re-mix product to regain a workable consistency but do not add any more water.
To maintain colour consistency, panels should be completed in sequence around the building.
Depending on the required finished thickness, a first pass is spray applied to a minimum thickness of 10 mm and ruled level. A second texture pass is applied between 1 and 2 hours after the first to form a single monolithic coat with a minimum thickness of 15 mm. Total finished thickness should be between 15 and 25 mm.
weber.pral M should be applied to the suitable substrate in a one or two-pass operation to a minimum thickness of 18 mm, or to a maximum thickness of 28 mm. (2 - 3 mm will be removed by the scraping process to give a finished thickness of minimum 15 mm, maximum 25 mm.) It should then be ruled level and allowed to harden for between 5 and 16 hours. (Sometimes a longer period may be necessary depending on weather and background conditions.)
When weber.pral M is green (set but not fully hardened) it should be scraped with a circular action using a scraping tool. It is essential that this is done carefully and evenly, ensuring all laitance is removed and that no part is missed. Thoroughly brush down the surface of the scraped finish using a soft bristle brush.
Apply weber.pral M in two passes to an initial thickness of between 20 mm and 28 mm to allow for an Ashlar recess from 2mm deep up to a maximum of 10 mm. Ensure a minimum of 15 mm thickness is maintained at the base of the recess for sheltered to moderate exposure. Rule level and spatula flat. When the material is still green, scrape the surface as detailed in the guidance notes for scraped finish.
Immediately after scraping, mark out and cut the Ashlar effect using weber Ashlar tools to produce the desired profile. Thoroughly brush down the surface of the render using a soft bristle brush. weber.pral M will set and gain hardness in a similar manner to conventional renders.
Protection from unfavourable weather conditions should always be provided during application and early age curing.
Do not apply:
Curing with a fine spray of clean water may be necessary during rapid drying conditions.
In hot climates, curing as above is essential for 3-5 days after application.
© 2008 - 2024 Plastering FX LTD. All rights reserved.
Company Registration Number 09913205