What length of decking boards should you choose for your patio? This is one of the most frequently asked questions by people planning to build a wooden patio. You can find boards up to 120 cm long on the market, but manufacturers and contractors often recommend shorter lengths. Why is this the case?

If you're wondering, what length slats for patio blinds When choosing, the answer depends primarily on the properties of the wood and the conditions in which the structure will be used. In this guide, we explain why For OpenUp Synem handles, we recommend lengths ranging from 40 to 110 cm, when 120 cm boards can be used and what solutions work best for larger openings.

Highlights

• The recommended length of slats for patio blinds is between 40 and 110 cm,
• 120 cm boards are available for purchase, but require greater attention when planning the layout,
• wood reacts to changes in temperature, humidity and sunlight,
• shorter boards are usually more dimensionally stable,
• Painted wood ages more slowly than unpainted wood, but it remains a natural material,
• for larger holes, it is worth considering division of the development into several modules or application aluminium slats.

„Why don’t you recommend 120 cm boards if you sell them?”

This is one of the most common questions we receive from people planning to clad their terrace with wood using OpenUp System slats.

The answer is simple: Boards measuring 120 cm in length are acceptable and are available in our range; however, based on the properties of the wood and our experience with installations, we recommend lengths of between 40 and 110 cm.

This is not due to commercial constraints or the design of the system. The reason is much simpler. Wood is a natural material that reacts to weather conditions throughout its entire lifespan. The longer the board, the harder it is to predict how it will behave after several seasons of exposure to sun, rain, frost and fluctuating humidity.

Key information about slats for patio blinds

• sets with 120 cm boards are available for purchase and can be used with OpenUp System brackets, however We do not recommend this approach. It should only be used in exceptional circumstances
• The recommended length of slats for patio blinds is 40–110 cm,
• shorter components are more dimensionally stable,
• Painted wood is more stable than unpainted wood, but it still expands and contracts,
• For larger openings, it is worth considering dividing the installation into several modules,
• For very wide spans, aluminium slats may be a good solution.

10 reasons why we recommend lengths of 40–110 cm

1. Wood is constantly changing

Wood absorbs and releases moisture from its surroundings. Fluctuations in temperature and humidity cause it to expand and contract naturally. The longer the plank, the greater the surface area affected by these changes.

2. Lower risk of bending

With the same cross-section, the shorter element retains greater rigidity. In practice, this means it is less prone to sagging.

3. Better resistance to sunlight

Long sections are more prone to uneven heating. One part of the board may behave differently from another.

4. Greater stability in response to changes in humidity

Wood reacts to changes in the environment, whether after rainfall or during hot weather. Shorter boards cope better with such cycles.

5. Reduced risk of twisting

The natural grain of the wood means that some pieces are more prone to warping. The risk increases with length.

6. Lower risk of cracks

The stresses that arise as wood dries are more easily distributed across shorter pieces.

7. Less strain on the handles

A longer board is heavier. This puts more strain on the mechanism and the mounting points.

8. More aesthetically pleasing buildings

Shorter sections tend to retain their straight lines for longer. This means that the cladding looks better even after several seasons of use.

9. Greater predictability

With lengths of 40–110 cm, it is easier to predict how the timber will behave over the long term.

10. Conclusions from the implementation

Over the years, we have installed numerous terrace, balcony and pergola enclosures. It is our practical experience that has shown that lengths of up to 110 cm offer the best balance between appearance, durability and functionality.

Does painted wood behave differently from unpainted wood?

Yes, but the differences aren't as great as you might think.

Painting or waterproofing:

• slow down moisture exchange,
• reduce the effects of UV radiation,
• improve the durability of the surface,
• slow down the wood's growth rate.

This does not mean, however, that wood ceases to be a natural material.

Painted wood it still reacts to temperature, humidity and sunlight, just as unpainted wood. For this reason, we also recommend lengths of up to 110 cm for painted timber.

Do you want to fit a door or window opening larger than 110 cm?

You have two tried-and-tested solutions.

Division of the development into several modules

This is the solution most often chosen by our customers. Instead of a single wide unit, you can create two or three modules with more practical dimensions.

Aluminium laths

If you need larger spans, aluminium is worth considering. Aluminium slats are more dimensionally stable and allow for wider modules than wood.

What would we choose for our own terrace?

If we were looking for wooden decking for a terrace, in most cases we would opt for lengths of between 80 and 100 cm.

This range works very well in practice. It allows you to preserve the natural look of the wood, minimise the risk of warping, and at the same time enjoy considerable freedom in designing your fitted furniture.

Summary

120 cm-long boards are available for purchase and can be used with OpenUp System brackets. However, we do not recommend this solution. They should only be chosen if the structure cannot be built any other way. Longer boards should not be used at all. Our recommendation of a length of 40–110 cm is based on many years of experience and the natural properties of wood.

If you’re not sure what length of boards to choose for your project, please get in touch. We’ll help you choose the right layout and number of modules for your terrace, balcony or pergola.