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Frequently Asked Questions

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Q. How do I clean my Low-e glass?

Hand Cleaning Low ’E’ Glass

Low ‘E’ Glass has a thin coating to the inner face of the glass. It is this hard and durable coating which gives the glass its thermal insulation and solar control performance compared to ordinary clear glass. The coated surface of Low ‘E’ glass DOES need to be cleaned differently too ordinary glass and the following guidelines are recommended for the best hand cleaning results.

Routine Cleaning

Hand cleaning of the coated (interior) surface of the Low ‘E’ glass to visibly remove accumulated dust or fingerprints, can be accomplished using a number of different glass cleaning products. The exterior surface of the glass is not coated and can be cleaned in the same fashion as ordinary glass.

Recommended Routine Glass Cleaning

A mixture of one part vinegar with ten parts water Vinegar based glass cleaners have generally demonstrated an ability to provide a clean and streak free glass surface. For persistent marks that are streaky with a purple colour, use Acetone. Always use a Glass cloth. Do not use ammonia based or alcohol based glass cleaners because these cleaners tend to leave visible streaks.

Routine Cleaning Procedure

Flood the glass surface with the spray on cleaning solution or with a cloth saturated in cleaning solution. Be generous with the amount of solution applied. Clean the wet area with a clean, lint-free towel or cloth. Wipe dry with a dry, clean lint free towel or cloth. DO NOT USE A SQUEEGEE on the Low’E’ coated (interior) surface. NO scraping with metal objects. To prevent streaking, stop wiping when the glass is almost dry and there is a uniform film of moisture left on the glass surface. Under no circumstances should razor blades or squeegees be used on the low E coated (interior) face of the glass.

Spot Cleaning

Occasionally, spot cleaning may be required to remove stubborn dirt or foreign material that may adhere to the Low ‘E’ coated surface. Spot cleaning products such as Acetone work to remove markings from grease, oil, tape adhesive and crayons or other waxy material as well as paint and rub-off marks from plastics.

Recommended Spot Cleaning Products .

Acetone (solvent available from hardware stores)

Spot Cleaning Procedures

Carefully follow the chemical manufacturers instructions Apply a small quantity of the cleaner listed above to clean, wet cloth or towel Rub on areas of glass needing spot cleaning Wipe clean using a dry, lint free towel or cloth followed by a routine cleaning procedure

Specialised Cleaning

Do not use razor blades, steel wool or other metallic objects on the Low ‘E’ coated surface. If metallic objects contact the coated surface, a thin layer of metal removed from the object may be deposited on the Low ‘E’ surface which results in a discoloured stain which is difficult or impossible to remove using normal cleaning procedures.

Recommended Specialised Cleaning Products

Hydrochloric Acid (available from hardware stores) diluted to 99% water to 1% hydrochloric acid

Specialised Cleaning Procedure

Carefully follow the chemical manufacturers' instructions Apply a small quantity of the specialized cleaner listed above to a clean, wet cloth or towel. A cotton bud may be used for thin line type marks. Rub on areas of glass needing cleaning Wipe clean using a dry, lint-free towel or cloth followed by a routine cleaning procedure. Ensure that the cleaner does not come into contact with framing materials.

Q. What are the benefits of Low-e glass?

Low-e Coatings (e stands for emissivity)

Available in both Single and Double Glazed units.

How Can You Become More Energy Efficient?

NB! The overall energy efficiency takes into the account the framing material used together with the glazing. Choose wood for the best result.

There are often different needs based on where you live, the orientation, your goals and how the sun's rays shine in your living room/s and other rooms. There could be a change in how you look at the usage of different areas of the house. How lighting might change, or how curtains and widow treatments will change. There are many aspects to consider.

Another concern is the initial cost but the long term savings in money spent on power in the home outweigh the increased cost over untreated glass and make LowE an economic choice.

Once your architect or competent person has done an assessment of your needs in each room in your home we can advise on how you can best achieve your ideal in regard to light and heat to make your home as bright and comfortable as possible in every season of the year.

What can you expect from Low-e glass? In summer, temperatures on the Highveld can rise to 30°C on the outside. Low-e coatings minimize the amount of damaging ultraviolet and infrared light and will limit the transfer of heat from direct sunlight to about 23°C or less and maintain it, thus reducing or removing the need for A/C 89°F= 30°C. 75°F= 23°C

In winter, when the High Pressure returns to the Highveld, inside temperatures can be maintained at about 20°C on sunny days, thus reducing the overall heating bill. On overcast cloudy days heating requirements will increase however for shorter periods to make the home comfortable 70°F= 20°C

Change to Low-e and live in a Brighter and More Comfortable Home Let us quote you for energy efficient windows and doors whether for a new project or replacement Please call if you need mouldings (Skirtings, architraves, dado rails etc.).

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Q. How can I make my home more energy efficient?

KPJ Understands Energy Usage in Buildings

SANS 10400-XA, SANS 204 & SANS 613

KPJ has an eight year history of studying energy efficiency. In fact, we helped to assist in the current fenestration regulations.

In 2007 we were invited to join the SABS building industry committee studying international energy efficiency regulations in order to find appropriate methods of employing their standards in South African climatic conditions. This committee met frequently for several years. We concentrated on the fenestration aspect and contributed to the decisions made which now appear in the National Building Regulations.

The goal for the home owner, worldwide, is to maintain a comfortable in house temperature of around 20°C summer and winter without additional heating or cooling.

Advanced technology has made this possible with the use of proper insulation for the building envelope. Glass is the major contributor to heat loss so it is critical to select the right glazing materials and fitment specialists.

This is where KPJ is highly knowledgeable in energy efficient techniques for the manufacture of wooden windows and doors. The added benefit for success is the reduction in energy consumption and costs.

The National Building Regulations (NBR) was gazetted and came into effect in September 2011 effective two months from date of notice November 2011 KPJ has more than met the SABS standards for energy efficiency. The majority of our products have been tested independently and certified (refer to the certificates on the web site) to be the highest quality available in South Africa Our testing is ongoing to maintain our high standards and that of the industry.

Please let KPJ answer any questions you have on energy efficiency.

Q. Does my Fenestration comply?

How are our competitors doing? According to AAAMSA’S “Registered Product Manufacturers” not very well, as it appears they are not taking the regulations very seriously if one looks at the lack of SANS 613 compliance .

A common question is why is it a big deal, why should I care? If you are building a new home or doing a renovation 10/1 your architect or competent person has spent a lot of time getting the building energy efficient.

A costly component of the build for increased energy efficiency is more expensive glazing.

The follow up question is how this affects me; my architect says I have the correct glazing!

The answer is when using a more expensive glazing or any glazing for that matter the unit (FRAMING + GLAZING ) also needs to be within the regulation of air and water leakage. (SANS 613)

In summary you may have the correct glass as specified but if the framing manufacture has not tested there products (SANS 613) you have no guarantee that the glass is doing the job of providing an energy efficient solution. Make sure you supplier has a SANS 613 certificate.

Thus, you have the confidence when specifying KPJ products that the investment in glazing is not money down the drain. You have peace of mind. See our SANS 613 certificates under our individual products on the KPJ web site.

The standard 4mm+12mm +4mm Double glazing (12mm Spacer has been found to be to most efficient) is now a growing demand as is single 6.38mm Low-e glass. We believe this trend will continue as homeowners look for the most energy efficient solution for their homes.

KPJ has a very good understanding and experience in the supply of energy efficient wooden windows and doors so if you need any information on this subject please let us know.

Q: Is your range limited in any way?

We try to satisfy all your requirements so if you do not find what you are looking for let us know via the CONTACT US Tab.

Q: What paint can I use for your products?

You can paint our products with water-based acrylic or mineral-based polyurethane paint products. Always follow the manufactures directions. Please note DARK colours are detrimental to EXTERNAL timber products and should be avoided. EXTERNAL products painted with DARK colours do not fall under the guarantee. Remember all six sides must be painted or oiled at all times to protect the timber and be covered by the guarantee. Always notify us if the product is going to be painted rather than oiled. Do not use a varnish on External product.

Q: Can you deliver and install the products I order?

YES we can. Installation done expertly by our qualified installers on request.