Garden furniture must withstand outdoor conditions. Use the right adhesives

The good weather is here, the days are longer and warmer and we want to stay outside more. As we still have to stay at home and even after 15 May it doesn't seem a good idea to go out in crowded places, balconies, terraces and personal gardens remain the safest places to enjoy the warm rays of the sun. From DIY stores or online, those interested can buy the furniture they want or the materials they want to make it from so that they can comfortably set up in outdoor spaces. Outdoor furniture made of wood or wood-based materials must be weatherproof and resistant to the sun's aggressive action, and it is not enough to protect it with outdoor varnishes, oils or paints. The adhesive used to make it must be specially formulated to withstand outdoor conditions.

Moisture resistance of adhesives

Adhesives are classified according to their chemical nature, the way they act, the reaction time or the strength of the resulting adhesive film. In the case of outdoor wooden furniture, the resistance of the adhesive film to outdoor conditions, especially moisture, is of great importance, as it is this that puts it at risk.

In terms of moisture resistance, adhesives, regardless of their nature, are divided into 4 resistance classes - D1, D2, D3 and D4. Class D1 adhesives are the least resistant to moisture, while class D4 adhesives are the most resistant. More information about the conditions that an adhesive in a particular category must meet can be found at here.

Wood specific adhesives are the aracite type, i.e. PVA (polyvinyl acrylic) adhesives, but other categories can also be used. However, PVA adhesives get on so well with wood that they are often called adhesives for wood, although they can also be used for gluing paper, textiles or other materials. Because in the past they were only used for gluing indoor furniture, there is still a reluctance to use them for glues that have to withstand high humidity. In the meantime, the resins used to make them have been improved and their bonding performance has increased. PVA adhesives are now commonly used for gluing bathroom or kitchen furniture, which are high humidity environments, or outdoors, where in addition to rainfall there is also the aggressive action of the sun.

Adhesives specially formulated to be moisture resistant

Szolvegy is the company that distributes the aracet brand of adhesives TISZABOND. The company's customers include manufacturers of hivesof solid wood panelsof houses on wooden structures or outdoor furniture. They use recommended adhesives that are suitable for the use and purpose of their products and thus manage to have satisfied customers.

For products used outdoors, Szolvegy recommends D4 adhesives because they are highly waterproof. They can be used for stacking wood, laminating elements, stairs, windows and doors, gluing panelling and assembling elements used in high humidity environments.

Here are three of the best-selling D4 adhesives:

TISZABOND 1kD4-D 4133 - one-component PVA adhesive. It has improved adhesion to the substrate, making very strong bonds with highly elastic film. The elasticity is due to the fact that the adhesive does not contain fillers (chalk, in general). Phe main characteristic of the adhesive, however, is its resistance to moisture. The adhesive film has very good impermeability, with moisture resistance comparable to a D4 adhesive with hardener. Although it is one-component it has a short pressing time, resulting in a solid, firm bond. It is resistant to external conditions and can be used for gluing laminated wood for windows, exterior wooden door panels and garden furniture.

TISZABOND 2kD4 4201 - two-component PVA adhesive. It is a highly resistant adhesive in wet conditions. It can also be used in construction, provided that one of the glued parts is wood (wooden concrete steps, wall window frames, etc). The film formed is elastic, very suitable for gluing solid wood which can have significant dimensional variations when the external humidity decreases or increases. When gluing hard and dense wood elements with low absorption, the adhesive is applied to both elements. For less dense woods it is sufficient to apply only to one of the elements. The adhesive is very suitable for window manufacturing and the quality certificate received from the Institute for Window Technology in Rosenheim, Germany, is a very strong argument for this. However, it is sensitive to contact with metals and can change colour.

TISZAPUR D4 4401 Special – It is one of the few adhesives in Szolvegy's portfolio that is not an aqueous polyvinyl acetate (PVA) dispersion. It is a one-component polyurethane adhesive that reacts with moisture in the atmosphere (therefore the packaging should not remain open when not working with it). It is highly resistant to extreme conditions and can be used to glue outdoor elements to be treated at high temperature and pressure in autoclaves. The reaction is considered complete 7 days after gluing, therefore it is not advisable to autoclave earlier.

How outdoor resistance can be increased

Even if the gluing is well done and the bonding film is strong, there are other causes that can lead to damage to garden furniture. Design elements, the finish used, winter protection, direct exposure to the sun are just some of the causes. Here are some suggestions to help you get the most out of your chosen furniture:

• Choose a pattern of elements that are not very close (not glued) to each other. That way water can run off and not splash on the furniture.
• Opt for simple finishes without film, oils or lacquers. Oils are the most suitable, even if the finish is retouched more often. If it's a film finish and it cracks, water gets underneath it and can do more damage than rain falling on furniture and dripping.
• Choose lightly coloured furniture. Pigments prevent the sun from reaching the wood.
• After rain, leave furniture outside in draughty areas to dry. If it's been covered, uncover it and let any condensation or moisture from the rain drip off.
• If furniture pieces can be moved, put them away in winter and cover them with plastic wrap or covers.
• Furniture lasts longer under an awning, under the shelter of a canopy or pergola, than in direct sun or rain.

May we have a beautiful and peaceful spring so we can enjoy the warmth of our balconies, terraces or gardens!