Maintenence

At the time of writing, all products come with standard manufacture material warrantees that also provide hand in hand with the applicator, providing the applicators are registered to use the product, material and labour guarantees that will rectify any defects if the material or application is found to be at fault.

Additional insurance backed guarantees can be obtained at additional cost if required.

We will carry out seamless render repairs and cleaning if required on any product regardless to whether we carried out the original work or not. Please phone for details.

We carry out all façade cleaning and acid washes. Note: The colour will very slightly fade after an acid burn.

We also provide written reports and carry out surveys with solutions to problems.

We have already repaired or over coated several new and old properties and found solutions to existing problems including sub-standard rendering carried out by others, we would be pleased to quote and rectify work to the standards that are expected.

In some instances where a new build property has multiple strait line cracking that exceed 2-3mm wide due to substrate failure, the only solution is for an elastomeric render over coat.

Tip:

Ensure control movement joints are present within the sub-strait where required.

Use steel Ladder Tore or similar within the blockwork bed joints above and below all openings and transfer the Ladder Tore to the vertical movement joints. This will strengthen a wall with many windows and transfer the stress to the movement joints. The larger volume of windows should be met with more Ladder Tore bedded in more mortar joints.

When block-coursing lifts are completed at the end of each day, ensure the top of the blockwork is washed/dusted off prior to laying fresh mortar otherwise this could result in horizontal cracking where the mortar has not bonded transferring through the new render.

We have carried out several repair, sub-standard and over coat solutions for the NHBC and supplied scaffolding, towers or cherry pickers to suit requirements with all building works required including painting with a silicon or Lotusan solution to enhance the finish.

Tip:

Please refer to the good practise guides when constructing new blockwork to ensure requirements are met for control movement within the substrate. This will enhance the life of the render and reduce or eliminate the possibilities of render cracking through substrate failure.

All expansion and contraction must be well designed into the substrate through control movement, deflection and compression whether constructing with steel frame, timber frame or blockwork.

Make sure remedial work, especially to through colour renders are carried out by experts otherwise you will have repairs that will look worse than the initial problem.

Product Maintenance for weber.pral Through-Coloured Renders

(Scraped finish & scraped ‘Ashlar’ finish etc)

Description weber.pral products are a range of low maintenance cementitious through coloured renders, with equivalent properties to mix designation III as described in The Code of Practice for External Renderings BS 5262 (1:1:6) = (cement : lime : sand).

We would suggest the products be applied by either Trained or Recommended Applicators as advised by our regional Area Sales Managers.

Cleaning The weber.pral range may be cleaned periodically by the use of a pressure washer incorporating a mild detergent or road traffic film remover in water. The spray pattern should be adjusted to form a fan rather than a jet and care must be taken at the exposed edges.

The interval between treatments is purely dependant upon the amount of ground floor pedestrian ‘traffic’ and local atmospheric conditions. Organic growth should be brushed off the surface and subsequently treated with weber CL150.

Repairs once applied weber.pral products are finished materials and repairs are always likely to be visible. For this reason we would, in general, recommend that full panels be removed and replaced. Where the elevation includes an Ashlar effect the cuts could be used as edges of the panel. Repairs will appear to be ‘new’ at first in comparison to the existing, but these should tone down and ‘weather in’ over period of time. The quality of the repair is very much based upon the skills and the patience of the tradesmen undertaking the works. The paragraphs below give solutions to specific issues when considering repairs:

Damaged Render weber.pral products are through coloured materials and as such small knocks and abrasions will not be as noticeable as with traditional painted renders. If a repair is deemed to be necessary, the material should be removed back to the substrate, a key provided by means of weber.rend aid and new material applied proud of surrounding surfaces. This should then be scraped back flush when the set allows. Please note that the existing render should be protected with masking tape to avoid staining.

Product Maintenance for weber.pral Through-Coloured Renders – Page 1 of 4 - 04/12/2007. For all small repairs including crack repairs weber ibocar can be used to accelerate the setting process of the weber.pral render and allow the scraping process to be completed shortly after application.

Cracking Please note for the prevention of cracking please see the Weber specifiers handbook under best practice section 7, crack control.

Straight line cracking is not typical of render failure, but rather of the reflection in the render of a crack in the substrate. The cause should be investigated prior to repair in order to ascertain the likely event of any further movement or whether remedial works are required. The works could include repairs to the substrate by pinning or resin bonding or introducing a movement joint. This assessment should be undertaken by a structural engineer.

BS5262 advises in clause 50.1 “inconspicuous cracks that remain dry and sound are usually best left alone. Cutting and repairing, however carefully done, invariably results in some differences in appearance over the area of the repair.”

There are three different methods of crack repair. Repair Systems 1 and 2 are designed for repairs to cracks where the issue of further movement has been assessed and is deemed remote or has been accommodated for by the introduction of an adjacent movement relief joint. The Repair System 1 method is an aesthetic repair to hairline/fine cracks and Repair System 2 is for cracks that are visibly open and any other forms of damage, requiring a patch type replacement. The final method, Repair System 3 is designed to allow for a small degree of further movement in the substrate. This repair method should only be undertaken by Weber recommended contractors.

Repair System 1

  1. Using a mini disc cutter run a cut through the crack in order to open the crack to the thickness of the cutter blade.
  2. Dry mix by volume 6 parts weber.pral with 1 part ibocar. Then add a dilution of 2 parts clean water mixed with 1 part weber adflex to produce a workable consistency. (Please note it is imperative that the weber AD230 to water ratio is measured correctly because, if the dilution is to strong, this will affect the finished colour of the repair).
  3. Fill the Weber cartridge with the mixed product and load into the cartridge gun. Cut the nozzle to suit the crack width and inject a bead of product into the crack ensuring that you do not overlay the material over the existing render but that you form a protruding nib of material 2 - 3 mm in front of the line of the existing render.
  4. Allow the repair material to stiffen for a period of between 20 - 40 minutes (dependent on temperature) then remove the nib carefully by using the edge of a small filling knife. If the scraping process is completed after the 40 minute period, it is likely that a much lighter shade of repair will be achieved than the existing render, which will not blend in.

Repair System 2

  1. Using a disk cutter cut a straight line 50 mm either side of the crack, then remove the render back to the substrate between the cuts.
  2. Stick a masking tape tight to the outer edges of the cut edges then prime the inside cheeks of the render cuts and exposed substrate with a dilution of 3 parts clean water and 1 part weber.tec latex.
  3. Whilst the primer is tacky skim a layer of mixed weber.pral including ibocar if desired into the void. Immediately push into the applied material a piece of Weber alkali resistant mesh cloth cut to width followed by a further coat of weber.pral applied over the mesh so as to fill the void and overlay the product onto the masking tape and past the existing thickness of render by 3 mm.
  4. Allow the product to pick up sufficiently until it is firm enough to allow for the scraping process and remove the 3 mm of excess product back to the line of the existing thickness Product Maintenance for weber.pral Through-Coloured Renders – Page 2 of 4 - 04/12/2007 of render. The edge of a filling knife could be adopted for this process.

Brush the product down to remove the scraping dust and remove the masking tape. Scraping too early or too late in the set of the material will affect the cured shade of the product and will prevent a colour match being achieved to the existing.

Repair System 3

  1. An assessment of the crack should be undertaken by a structural engineer to evaluate the degree of movement required. If the expected movement is greater than would be reasonably expected from the expanded metal lath within the render, then consideration should be given to the inclusion of a designed movement joint within the substrate and render.
  2. Using a disk cutter cut a straight line at least 150 mm either side of the crack, then remove the render back to the substrate between the cuts. Stick a masking tape tight to the outer edges of the cuts to prevent staining of the existing rendering.
  3. Mechanically fix a light expanded metal over a polythene sheet to the exposed substrate and embed in a 10-12 mm undercoat of weber.rend PUC, and scarify to produce good key. Leave for a minimum of three days to cure.
  4. Prime the surrounding edges of the existing render with a dilution of 3 parts clean water to 1 part weber.tec latex to avoid a dry joint between old and new materials. Whist the primer is still tacky apply a coat of weber.pral over the weber.rend PUC so as to fill the void and overlay the product onto the masking tape and past the existing thickness of render by3mm.
  5. Allow the product to pick up sufficiently until it is firm enough to allow for the scraping process remove the 3mm of excess product back to the line of the existing thickness of render with a Weber scraping float. Brush the product down to remove the scraping dust and remove the masking tape.

Site work

BS5262 Code of Practice for External Renderings and BS8000, Workmanship on building sites, Part 10, Codes of Practice for Plastering and Rendering, should be followed at all times.
Painting The weber.pral range are low maintenance products that do not require painting. However, if painting were deemed to be necessary any exterior masonry paint suitable for cementitious materials, e.g. Weber.plast P would be in order.

The above information is applicable for the weber.pral group of products.

weber.pral D weber.pral H weber.pral M weber.pral MF

The application of Weber.sil P to weber.pral M/H/MF Monocouche scraped finished renders

weber.sil P is a high performance mineral paint that gives exceptional long term durability and performance. It is anticipated that the use of this product will not detract from the low maintenance benefits of the weber.pral monocouche render. Providing that the Monocouche render is clean, dry and sound, a direct application of the weber.sil P is appropriate.

Product Maintenance for weber.pral Through-Coloured Renders – Page 3 of 4 - 04/12/2007

The first coat of weber.sil P should be diluted with between 10% and 15% clean water and the paint then applied with a medium pile wool paint roller. When the first coat is dry 6 -24hrs later a second coat is applied, again this coat should be diluted with water between 5 and 10%.

The application should be in a criss-cross pattern ensuring that the paint is applied evenly minimising any effect on the scraped texture of the Monocouche.

Please note when the product is applied to a sprayed roughcast texture brushes may need to be adopted for the method of application.

weber.sil P is manufactured in the colours shown in the Monocouche Renders guides. It is important to note that the weber.sil P colours have been matched to our internal factory quality control colour specification for the render colours. However, there are many influencing factors surrounding the application of the Monocouche render that will affect the final cured shade of colour; in particular the point at which the laitance is removed by scraping in the setting process of the render. Due to this it is therefore not possible to always ensure an exact match to the shade of colour achieved at the job site.

Spillages do stain and are difficult to remove so protect vulnerable areas thoroughly and wear suitable protective clothing. Tools can be cleaned with clean water.

Gypcom Limited
Unit 2, G3 Business Park
Dolphin Road
Shoreham-By-Sea
Sussex, BN43 6AN

Tel: 01273 591725
Fax: 01273 911009
Email: info@gypcom.com

VAT no. 785 5813 83

Specialist rendering to the construction industry using cementitious, acrylics, silicon’s and eco renders, machine and hand applied.