Glass balustrades are best suited when an unobstructed view and a more cohesive windbreak are key considerations. Horizontal slats are appropriate when you want more structure, privacy, and a more clearly defined look—but the horizontal slats must be designed with special consideration for the risk of climbing.
Both options can be used as part of a safe decking balustrade, but the choice of materials is only one aspect of the design. Height, openings, fixing, and layout also need to be adapted to the location and how the deck is used.
In this guide, we compare horizontal slats and glass based on views, drafts, privacy, child safety, and maintenance, so you can more easily decide which option is right for your deck.
What is the difference between horizontal slats and a glass balustrade?
Horizontal slats provide more structure and can create greater privacy, but horizontal elements can also serve as footholds for climbing. Glass preserves the view better and provides more continuous protection from the wind.
On a deck, the decision must therefore be based on safety, the view, wind, privacy, and the level of maintenance you're willing to handle.
| Property | Horizontal slats | Glass balustrade |
|---|---|---|
| Appearance | Distinct horizontal lines, texture, and a more defined frame. | A visually lighter and more open look, especially with clear glass. |
| View | It depends on the width, spacing, and position of the slats in the field of view. | Clear glass preserves much of the view. |
| Wind | Air can pass between slats. | More continuous wind protection, but air can pass around the edges and openings. |
| Overlooking | A denser slats provide more privacy but reduces transparency and airflow. | Clear glass provides little privacy; frosted glass can reduce overlooking. |
| Climbing risk | Horizontal slats can provide a foothold for climbing. | The glass infill lacks horizontal rungs, but the entire railing must be evaluated. |
| Child safety | The lower section should prevent climbing, and any openings must not pose a risk. | There are no openings in the glass panel itself; however, the height, clear dimensions, glass, and fixings still need to be evaluated. |
| Maintenance | Wood requires periodic surface treatment; aluminium mainly cleaning and inspection. | Cleaning and inspection; fingerprints, pollen, and water spots are often more visible. |
What are the advantages and disadvantages of horizontal slats for deck balustrades?
The main advantage is the aesthetic appeal: a horizontal slats gives the deck distinct horizontal lines, structure, and the potential for greater privacy. The disadvantage is that these same horizontal elements can provide a foothold and therefore must be designed with special consideration for the risk of climbing.
The advantage
The lines create rhythm and a sense of seclusion
Slats define the edge of the deck and give the balustrade a stronger visual character. Their width and spacing affect the view, airflow and degree of privacy between them.
The downside
Horizontal sections can provide a foothold
Horizontal slats can serve as a climbing aid. In areas where younger children are likely to be present, the lower section of fall protection must therefore be designed to prevent climbing.
One possible approach
Break the horizontal rungs in the lower part of the railing
One way to maintain the horizontal appearance is to design the lower section without horizontal elements that provide a foothold – for example, using a solid fill or vertical elements – and to let the horizontal slats begin higher up.
This principle does not automatically make the design suitable as a fall protection. The height, openings, fixing, and other aspects of the railing's design still need to be evaluated together.
Choice of materials
How do the wooden and aluminium versions of " slats " differ?
- Slats made of wood
- Wood has a natural look but needs to be inspected and treated periodically. How often depends on factors such as the type of wood, the finish, weather conditions, and how exposed the railing is.
- Slats made of aluminium
- Powder-coated Aluminium does not need to be oiled or treated with a protective coating in the same way as wood. Surfaces and fixings still need to be cleaned and inspected as part of routine maintenance.
If you want a slatted, more defined look but less frequent surface treatment, an aluminium balustrade may be worth comparing with timber.
When is the best time to wear glass balustrade on the deck?
Glass is best suited when an unobstructed view and a more cohesive windbreak are more important than the need for a slatted design. A glass balustrade for a deck can therefore be a good choice on an open side where you want to preserve the view but reduce the amount of wind that passes directly through the railing.
The main advantage of glass
Unobstructed views with more continuous wind protection
There are openings between the horizontal slats through which air can pass. A continuous glass panel therefore shields from the wind in a different way without simultaneously blocking the view with dense, opaque sections.
The glass panel also lacks horizontal rungs and openings in the panel itself. Nevertheless, the entire railing must be evaluated based on, among other things, height, glass type, clear dimensions, and fixings.
Views and privacy
What type of glass surface is best for the deck?
Clear, frosted, and tinted glass primarily affect how much you can see through the railing, how much overlooking is reduced, and how bright the railing appears.
- Clear glass
- Preserves most of the view and lets in plenty of light. It’s ideal where the surroundings are an important part of the patio and there’s little need for privacy screen.
- Frosted glass
- It limits visibility while still allowing daylight to pass through the glass. It can be installed on a side facing a neighbour, a street, or another area where you want more privacy.
- Tinted glass
- Provides a darker and more distinct look than clear glass and can reduce the feeling of being overlooked without completely blocking the view.
The glass's construction is a separate choice
Clear, frosted, and tinted primarily describe the appearance of the glass. Lamination, on the other hand, refers to the glass’s structure. Laminated glass is held together by an interlayer if it breaks. The type and thickness of glass required must be determined in conjunction with drop height, fixing, and the rest of the railing structure.
How much maintenance does glass require?
Glass does not need to be oiled or treated with a protective coating, but dirt is more visible on its transparent surface. Fingerprints, pollen, and water spots can therefore make it necessary to clean the glass more often than a slatted balustrade. Profiles and fixings also need to be inspected as part of routine maintenance.
What should you consider with horizontal slats and glass balustrades where children use the deck?
In areas where younger children are likely to be present, the railing must be designed so that the lower section prevents climbing and so that openings do not pose a risk. A continuous glass panel makes it easier to avoid horizontal climbing steps, while horizontal slats require greater care in the lower section of the railing.
The required balustrade height depends on how the site is used, drop height and the requirements for the project. The height and design must therefore be assessed based on the overall fall protection system.
Child safety
Three safety considerations to check
Climbing, openings, and the distance to the floor are important aspects of the railing's design. They must be evaluated in conjunction with the entire structure and the requirements applicable to the location.
- Climbing
- Make sure that horizontal parts, fixings, and protruding elements do not create easily accessible footholds for children.
- Openings
- Assess the size and placement of the openings so that children do not run the risk of falling through or getting stuck in the railing.
- Bottom edge
- Check the distance between the bottom of the railing and the floor, so that the opening does not pose a risk to children.
What does this mean for your choice?
Slats and glass have different characteristics
Horizontal slats
Horizontal slats can provide a foothold. The lower section must therefore be designed to prevent climbing, while the openings and other dimensions must be suitable for the specific structure.
Glass
A continuous glass panel has no horizontal climbing rungs and no vertical openings in the panel itself. However, this does not mean that the railing is automatically child-safe – the height, clear dimensions, glass, and fixing must still be correct.
Measure from the correct level
Balustrade height is measured from the finished deck floor to the top of the railing. Drop height is measured from the deck level to the lower level below.
Can you combine slats and glass on the same deck?
Yes, different parts of the deck can have different types of screening depending on what’s needed on that particular side. Glass may be suitable where the view and windbreak are most important, while slats can provide more privacy on a side where overlooking is more of a concern.
Different functions on different sides
Let the needs of each area determine the infill
Glass on the side with the view
On the side facing the view, glass can preserve visibility while providing more continuous protection from the wind.
Slats where you want more privacy
When facing a neighbour’s property or another more exposed side, slats can provide a clearer sense of space and limit visibility to varying degrees depending on width and distance.
The combination must be planned as a whole. Do not assume that the same posts, fixings, or other structural components can automatically be used for both glass and slats —each component must be designed for the specific solution.
What should you consider when choosing between slats and glass?
Start by considering safety and the conditions of your patio. Then you can weigh the pros and cons of views, wind, privacy, and maintenance to determine whether glass, slats, or different solutions for different parts of the patio are the best fit.
Before you make up your mind
Review these points
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Assess the height of fall and the need for fall protection
Start with the level of the finished deck and the lower level below it. The drop height and how the deck is used affect the requirements that need to be taken into account regarding the railing’s height and design.
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Consider whether younger children can be on the deck
Horizontal slats can provide a foothold and must therefore be designed with special consideration given to the risk of climbing. Glass panels lack horizontal climbing rungs, but the safety of the entire railing must still be assessed.
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Check which direction the wind comes from
If a side is particularly exposed to wind, a continuous glass surface may provide better wind protection there than an open slatted structure. Keep in mind that wind can still pass around the edges and openings of the railing.
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Check the view from a seated position
Sit where the dining table or lounge furniture will go and assess the field of view from that spot. A horizontal “slat” may end up right in the middle of the view, while clear glass has a much smaller impact on the view.
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Decide how much overlooking you want to prevent
The width and spacing of the slats can provide varying degrees of privacy. With glass, the choice between, for example, clear and frosted glass affects how open the railing feels and how much overlooking is reduced.
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Allow for future maintenance
Wooden slats require periodic surface treatment. Aluminium slats and glass primarily require cleaning and regular inspection, but dirt and water spots often become more visible on a transparent glass surface.
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Measure all sides before deciding on the railing
Measure each side of the railing and check how the corners meet. On a deck with multiple angles, you’ll also need to distinguish between inside corners and outside corners when planning the measurements and the railing’s placement.
Brief summary
Glass is most effective when views and windbreak are prioritized, while slats offer greater opportunities to create structure and privacy. Safety and the site’s conditions should always be the guiding factors before the design aesthetic determines the choice.
Do you need a new balustrade for your deck?
Once you've carefully considered safety, views, wind, and maintenance, you can compare railing options based on what works best for your specific deck.
What are the most common questions about horizontal slats and glass balustrades?
Common questions concern child safety, wind protection, maintenance, balustrade height, glass construction and the privacy each option provides.
Are horizontal slats safe in areas where children are present?
Horizontal slats can provide a foothold and must therefore be designed with special consideration for the risk of climbing. In areas where younger children are likely to be present, the lower part of the railing must be designed to prevent climbing.
Which offers better wind protection – slats or glass?
A continuous glass surface typically provides better wind protection than an open slatted structure, since air can pass between the slats. Wind can still get around the edges of the glass and other openings in the railing.
Which requires the least maintenance— slats, or glass?
It depends on the material. Wooden slats require periodic surface treatment, while aluminium slats and glass mainly need to be cleaned and inspected. Fingerprints, pollen, and water spots are often more visible on glass.
How high should a deck balustrade be?
The height of the railing needs to be adjusted based on how the deck is used, drop height and the requirements that apply at the site. Therefore, evaluate both the height and the overall design of the fall protection system before choosing a railing.
What type of glass should be used in a decking balustrade?
The glass’s construction and thickness must be selected in conjunction with the railing’s fixing, design, and drop height. Laminated glass has an interlayer that helps hold it together in case it breaks, but the right solution must be determined for the entire balustrade system.
Can you combine slats and glass on the same deck?
Yes, different parts of the deck can be designed to meet different needs. Glass, for example, may be suitable where the view and windbreak are most important, while slats can provide more privacy on another side. Each part needs to be designed for the specific structure.
Do horizontal slats provide good privacy?
Slats can provide more privacy, but the effect depends on their width, distance, and viewing angle. Closer spacing reduces overlooking more but also affects transparency and airflow.
