FAQ – Frequently asked questions

The recommended size of the gutter system can be calculated using the nomogram located in the Download section/Technical and information aids. If you need to consult the given calculation, contact our sales outlets.

The difference between a semicircular gutter system and a square gutter system lies in their shaping, aesthetics and functional properties.

Semicircular gutter system: thanks to its rounded shape, it drains water more efficiently and prevents the accumulation of dirt. The rounded profile enables faster water drainage, which reduces the risk of clogged gutters.

Square gutter system: it may have more capacity to trap water, but due to the sharp corners, there is a greater chance that dirt will be captured in it, which can slow water drainage.

In our offer you will find a wide range of materials and surface finish treatments from glossy colours to matte ones. You can find the sizes and complete colour palette of the gutter system in the section products/semicircular or square gutter system.

With proper installation and maintenance, the aluminium gutter system will provide reliable performance for many years.

In KJG, we exclusively specialize in the production of gutter systems and roof coverings of metal materials such as: galvanized steel, aluminium, titanium zinc, copper and stainless steel. Plastic gutter systems are not part of our offer.

It is not possible to order an atypical size and length of roof gutters or downpipes. We offer only standard sizes and lengths that are adapted to the most frequent requirements of customers and construction projects. If you need other lengths or sizes, it is necessary to modify the products directly at the installation site.

The minimum slope of roof gutters should be approximately 5 mm for each metre of the length of the gutter, representing a slope of 0.5 %. This slope ensures an efficient drainage of water towards the gutters, thus preventing the accumulation of water and possible overflow of the roof gutters.

Standard: STN 73 3610 Tinsmith construction works

The distance between the roof gutter brackets should be optimally 60 to 90 cm. In areas with high snow or wind loads, it is advisable to reduce this distance to approximately 50 cm to ensure higher stability and resistance of the gutter.

At critical points, such as the corners and ends of gutters, the brackets should be placed even closer, usually within 10 to 15 cm from these locations, to avoid deformations.

We bend the roof gutter brackets in KJG shops according to the attached drawing, but we recommend that the final bending should be carried out directly at the construction site, where the brackets can be adapted to the specific conditions and needs of the roof.

We do not offer roof gutter brackets for fastening from the side of the rafters. Our offer of brackets focuses on other types of fastening that are adapted to our products and installation specifities.

If you have specific fastening requirements, we recommend contacting our professionally trained staff at KJG shops that will help you find the most suitable solution for your project.

In our offer you will find a wide selection of roof coverings that are adapted to different types of buildings and customer preferences. In the section Products/Roofing you can find all types of roof covering.

The material versions of our roof coverings differ according to the type of covering. You can find a complete overview of available materials and variants in the section Products under the category Roof coverings.

We will be happy to advise you in choosing the optimal material for your project.

The covering widths of roof covering sheets are as follows:

Metal roofing UNI 1: 1105.0 mm

Metal roofing UNI 2: 1100.0 mm

Trapezoidal sheet roof TR 18A: 1100.0 mm

Trapezoidal sheet roof TR 35A: 1060.0 mm

Roof covering KJG FALZ: depending on the coil width

Roofing panel CLICK 205: 205.0 mm

Roofing panel CLICK 306: 306.0 mm

Roofing panel CLICK 515: 515.0 mm

The maximum manufacturable lengths of coverings are as follows:

Metal roofing UNI 1: 8400.0 mm

Metal roofing UNI 2: 8400.0 mm

Trapezoidal sheet roof TR 18A: 8000.0 mm

Trapezoidal sheet roof TR 35A: 8000.0 mm

Roof covering KJG FALZ: depending on the roof design

Roofing panel CLICK 205: 8000.0 mm

Roofing panel CLICK 306: 8000.0 mm

Roofing panel CLICK 515: 8000.0 mm

You can find all the minimum slopes of the roof coverings in the download section /technical and information aids.

We provide a profiling service directly at the site of the building unit. Our trained staff will bring the profiling equipment together with the necessary construction material, where it will then perform the profiling of the required profiles at site.

In this way, we can ensure efficiency and adapt to specific conditions of the construction.

The difference between the folded roof covering and the CLICK roof covering lies mainly in the method of installation and aesthetic properties:

Roof covering KJG FALZ (classic folded roofing) is a traditional type of sheet metal covering, where individual sheets are connected by the so-called double fold (bend). This method of installation requires experts, because folding is done by hand or using special machines. The folded roof covering is very resistant to weather conditions, also suitable for roofs with a very low slope, and it has a classic, elegant look.

Roof covering KJG CLICK system is a modern type of roof covering which is installed easier thanks to the so-called CLICK system. This system allows you to click individual sheets into each other without the need for manual folding. The installation is quicker and manageable even without special equipment. The roof covering CLICK has a clean and modern look, but it is not always as resistant to extreme conditions as classic folded roofing.

You can find all types of snow catchers in the section Products under the category Snow catchers. They are divided according to the type of roof covering, which will make it easier for you to choose the right catcher for the KJG roofing.

If you need advice on choosing, do not hesitate to contact us.

When installing KJG roof coverings, it is important to take into account temperature conditions, because low temperatures can affect the properties of materials and the quality of work.

In general, it is recommended to carry out the installation of sheet metal roofing at temperatures above +5 °C.

At lower temperatures, increased material fragility may occur, increasing the risk of damage during installation.

In addition, at temperatures below the freezing point, there may be problems with sealing and applying sealants that may not adhere or cure properly.

We offer standard flashing which we have in stock and also custom flashing which we can make exactly according to your requirements and technical specifications.

The conditions for returning the goods are set as follows: the goods must be in their original, undamaged packaging and must be completely intact to meet the criteria for taking back. Furthermore, it is necessary that the returned goods belong to the standard assortment of the KJG network because these conditions do not apply to specially or individually ordered goods. For each return, we charge a handling fee of 30 % of the value of the goods, which covers the costs associated with reprocessing and taking into storage.

We do not install gutter systems and roof coverings, but we can recommend a reliable implementation company that can help you with this. You can contact our sales outlets, where we will be happy to advise you on the right choice of the implementation company.

We recommend that you remove the protective foil from KJG products as soon as possible within 7 days from installation at a temperature of 5 °C to 40 °C.

You can buy KJG products directly in our shops or from our authorized branded dealers who are regularly trained and have the necessary information to advise you on choosing the right products. At present, we do not sell our products through the e-shop, which allows us to provide personal access to each customer, where you can see and consult the products with experts at site. In this way, we can guarantee the highest quality and proper application of our products.

Yes, it is possible to purchase even small quantities from us, starting from 1 piece. At all KJG points of sale we try to meet the needs of various customers, including those who need smaller quantities of goods.

We have standard products in stock, while others are available to order. The delivery time depends on the quantity and type of material.

For accurate information, we recommend contacting KJG sales points directly, where we will be happy to provide you with specific details.

Yes, we offer a lightning conductor system of the German brand DEHN. In the section Products/roof accessories you can find a wide range of products.

In our offer you can find up to 6 types of roof foils, which are suitable for various types of roofs and ensure reliable protection against moisture and weather conditions. You can find a complete selection of all roof foils, including detailed information about their properties and use, in the section Products under the category roof accessories.

We offer roofing foils exclusively in whole packages, which ensures optimal quality and protection of the material during transport and storage. In this way, we can guarantee that each package contains a sufficient quantity of foil for your projects, without residues and waste that could be formed when buying in smaller sections.

Yes, we can deliver the goods to the desired place. We have our own fleet of vehicles, including cars up to 3.5 t, vehicles with hydraulic arm, with hydraulic platform, and trucks.

You can order transportation at our sales points when buying KJG products.

There are benders in our shops, where you can bend the sheet metal yourself according to the desired profile, or it can be bent by our trained staff to order. All types of benders can be found in the section Services/Bending centre.

The sheet metal which has not been purchased from us cannot be bent at our site.

We offer the bending service exclusively for the sheet metal purchased directly from our KJG shops to guarantee material quality and compatibility with our machine equipment.

As far as the exact delivery time concerned, we recommend contacting directly a KJG shop where the order is placed so that we can take into account all the details of your requirements and set an exact delivery date.

We offer roll bending services for folded roof covering only, which is specially designed for this type of processing, thus we guarantee high quality of the final product. However, we do not roll standard sheet metal, we only bend them. If you have specific requirements for rolling the folded roof covering, we will be happy to provide you with more information about the options and available formats.

With us, you can rent basic tinsmith tools, such as tinsmith shears, fold closers and more. If you prefer to buy, you can find the complete range of tinsmith tools in our section Products.

You can also buy from us as a private person. Our products and services are available not only for companies and self-employed people, but also for individuals who need materials for their own projects or home repairs.

For the convenience of our customers we accept payments by credit cards at all our KJG shops to make the purchase quick and trouble-free.

Unfortunately, it is not possible to pay an invoice or an advance invoice with us using a payment card. Payment of these documents should be made exclusively by bank transfer or other agreed method that supports non-cash payment.

The company KJG a.s. offers combined services, such as transport, profiling and bending of materials, which may have a different tax regime than the sale of goods itself and are subject to different tax rules, for this reason it is necessary to divide these items into separate documents.

We do not directly make chimney caps, but we will be happy to recommend an experienced tinsmith who can custom make them for you according to your requirements. Just contact us and we will provide you with a contact to an expert who helps you with the solution.

To prepare a quotation for the roof covering and gutter system, we will need project documentation that contains all the necessary technical and design data about the roof. This document should include details such as roof size, slope, type and choice of materials, as well as the location of the gutter system and other specifications that are important for proper computational analysis.

Based on this documentation, we can accurately prepare a quotation that will meet your needs and requirements.