How to make trellis panels

Three examples of sturdy, long-lasting, DIY trellis panels

TRADITIONALLY, trellis is any open framework used to partition areas of a garden or support climbing plants. In principle trellis — which comes from the latin for “arbor” or “summer house” — can be made out of any suitable materials: Metal, wood or even pierced-brick-walling could rightly be called trellis, but for the purpose of this post I am going to look at simple timber trellis panels that can be used as screens, garden dividers or added to fences to increase their height. Creating a set of trellis panels is an easy weekend DIY project, which, given a little planning and care can produce very satisfying and durable results as well as saving money along the way.

Why DIY?

The limitations of pre-made trellis

If you can find pre-made trellis that suits your needs then there is little reason to go to the trouble of making your own. However, the typical timber trellis sold in garden centres suffers from a number of shortcomings which are avoidable if you make your own trellis from scratch:

  1. FRAGILE Often made of thin, light-weight timber which will not last.
  2. LIMITED SIZES Only available in a limited range of sizes. If you need trellis of different dimensions you will have to bodge something.
  3. LIMITED DESIGNS Only available in limited design/proportions/timber dimensions.
  4. EXPENSIVE Typical trellis panels are roughly twice the cost you could make them yourself.

Here is a typical example of a trellis panel from a UK garden centre…

Panel size: nominally, 6ft x 2ft; Timber: 18mm x 36mm treated batons; Cost: £14.95

The trellis above is made from the smallest dimension tile-batten (18mm x 36mm) which is cheap and easy to pick up from your local timber merchant. You would need 44ft in total (13.5metres), which is you can get for approximately 50p per metre. So DIY costs would be closer to £7.50, i.e. about half the cost of the pre-made panel.

DIY Trellis Using Tile Batten

Tile batten (aka timber roof batten) is a widely available treated timber, commonly used in the roofing trade to support roof tiles. As such it is a bulk product, reliable and cheap. You should be able to phone up your local timber merchant and purchase it in bulk. Alternatively, Wickes and other DIY stores can supply and deliver, although they tend to be a little bit more expensive than trade merchants.

When it comes to DIY, you can choose the lengths and dimensions of batten that will suit your project. This way you can make sure the finished trellis is exactly the dimensions and weight you want.

Typical Tile Batten dimensions

Dimensions (cross section), (mm)
[imperial equivalent, inches]
Typical costTypical lengths, (m)
[imperial equivalent, feet]
19 x 38 [¾” x 1 ½”]
25 x 38 [1″ x 1 ½”]
25 x 50 [1″ x 2″]
£ 0.50 /m
£ 0.80 /m
£ 1.10 /m
2.4 [8′]
3.0 [10′]
3.6 [12′]
4.2 [14′]
4.6 [16′]
5.2 [18′]

What to watch out for when buying tile batten

  1. Tile batten dimensions are nominal. Batten can vary in size between suppliers by +/- 2mm so order all you need in one go.
  2. Don’t rely on imperial dimensions. For example, when builders or timber merchants refer to “10ft battens” these are actually 3m, i.e. 9.8 ft not actually 10ft.
  3. Remember that each saw cut loses you a few millimetres; so, for example, you can’t get 4 x 60cm lengths from a 2.4 m piece. If you try you will find the last piece will be closer to 59cm long.

Planning your Trellis

Slat spacing

Vertical and horizontal slat spacing will determine the look of the trellis. If the spacing is equal vertically and horizontally then the holes produced will be square. If the vertical and horizontal slats spacings are not equal then the holes will be rectangular, or even slits.

Overall, wider spacing will create a lighter look, allowing more sun and wind to pass through. Tighter patterns, with the slats closer together, create a denser, more textural pattern.

Another point to bear in mind is that the pattern looks different depending which side the trellis is viewed from (more on this below)

Effects of Slat Spacing on Light, Privacy and Sight-Lines

The open nature of trellis produces dappled shade when the light comes from certain angles. More open designs obviously allow more light to pass through the trellis, but the thickness of the structure means that this is only true when illuminated fairly straight on. At more oblique angles light penetration diminishes rapidly. However, at these angles the trellis itself can be illuminated dramatically.

In terms of privacy, trellis is never going to prevent views through. Nevertheless, it is only possible to see though when viewed from a narrow range of angles either side of straight on, because at more glancing angles the thickness of the trellis blocks the view.

Where privacy is paramount, a third set of slats can be fixed to the back, blocking the view through, but still letting air pass.

Effects of Slat Spacing on Wind Loading and Microclimate

The openness of the trellis determines the amount of wind that will pass through and the force exerted on the posts and panels. Trellis experiences far less force from the wind than the same area of solid fence because the wind can pass through it’s multitudinous openings. The greater the percentage of “gap” in the design the less the force the wind will exert in a gale.

Another factor to consider is wind baffling. When air passes through openings the air flow is broken up, significantly reducing wind speed. Trellis can, therefore, improve the microclimate in your garden by slowing the wind. A solid fence is actually much less effective in this regard as air striking a solid obstacle it is forced to go over the top creating sharp turbulent gusts on the far side. A 50% openness is considered optimum for reducing wind speed as air that passes through is maximally disrupted and will most effectively reduce wind speed. Trellis with more than 50% ‘holes’ will allow more air to pass through and will slow it less. Likewise, below 50% more air will be forced over the top of the trellis causing gusts on the far side and increasing wind load on the panel.

Vertical and Horizontal Sides of the Trellis

Depending which side you view it from trellis will emphasis the vertical or horizontal slats. The two photos below are of the same panel of trellis which has simply been turned round.

This effect is most evident when viewed from oblique angles or when illuminated obliquely by the sun. In the photo below I chose to have the vertical slats forwards to harmonise with the vertical slats of the fence panels. As you can see the effect is quite subtle when viewed head-on.

I made square trellis for the top of the fence along my vegetable garden. It looks great with the trained fruit I grow here.

Square trellis

Square trellis has a traditional look which is never out of place in the garden. Notice how the close-spaced designs produce a strong geometric pattern which looks quite different depending on the side that is viewed. This becomes gradually less significant as the slat spacing increases.

Several designs of square trellis showing different slat spacing
Slat spacings indicate the size of the gap compared to the size of the slat. So a 1:3 spacing means the gap is three times as wide as the slat. The openness indicates the percentage of the area that is “gap”. The diagrams show the two sides of each design with (left) the vertical slats facing forwards, and (right) the horizontal slats facing forwards.

Horizontal Trellis

Keeping the horizontal slat spacing tight whilst moving the vertical slats further apart, leads to various forms of rectangular slot being created. Compared to the traditional square trellis this horizontal arrangement produces a more modern look, especially when viewed with the horizontal slats to the front (see the right-hand diagrams below).

By keeping the spacing of the horizontal slats tight (1:1) and increasing the spacing of the vertical slats a pattern of slots can be created.

Trellis Screen Designs

If the gaps between slats are made significantly narrower than the slat widths then the panels will look less like trellis and more like a continuous panel. Such designs work well as full height fence panels and produce a very modern look.

Closely spaced battens produce a modern look, especially when arranged horizontally. Less like trellis, such panels make good garden walls when placed over fence panels.

Made as full-height panels (e.g. 2m/6ft) these could easily be fixed to the front of existing fence panels to create a new, modern looking fence around your garden. Commercial versions of similar panels are often made from cedar and have a very high price tag. Tile batten is much cheaper and can be given a similar look if stained, painted or by sanding the front of the panel. If you decide to go down this route bear in mind that tile batten often contains knots whereas cedar is generally knot-free. Knots can be reduced by selecting sections of batten that are clear, although this leads to considerable wastage.

DESIGN IDEAS: Examples of slatted screening I found on Pinterest

Practical Considerations of Slat Spacing

The slat layouts above (square or horizontal) assume that your trellis panels can be just the right width and height to accommodate such slat spacing. Generally they will not and you will need to work backwards, dividing the width and length available to achieve approximately the spacing you want. Once you have worked out the spacing approximately you can find the exact spacing as you build the panels as shown below:

  1. Measure and cut the top, bottom, left and right slats and screw/nail them together (Top diagram)
  2. Check the frame fits the space required — it is easier to alter now before you cut and fit all the other slats!
  3. Carefully measure the height from the top of the top slat to the top of the bottom slat (See * above)
  4. Divide this by the number of “holes” you want vertically (3 in the example above)
  5. Mark off these lengths as indicated.
  6. Attach the horizontal slats using these marks to align their top edges
  7. Repeat for the width of the panel, marking off equal spaces for the vertical slats

TIP: To start with only fix each slat around the perimeter of the panel. This gives you the opportunity to step back and spot any mistakes you have made. If everything is OK you can then fix screws/nails at all the other junctions.

Construction Tips

In this project below I used 50mm x 25mm batten which I ordered from Wicks who delivered next day. Their batten was stained a bright blue, but I intended to paint it, so that was no a problem.

1. Painting the Battens

If you are not painting your trellis skip this step!

If you intend to paint or stain your trellis it is easier to do so before cutting up the battens and much easier than trying to paint a fully assembled trellis panel. I used Sadolin Quick Dry Ebony stain.

2. Cut the Battens to Length

When making panels to fit existing structures (fence posts etc) it is better to make each trellis panel individually. Measurer the space carefully and leave a few millimetres so you can get it in without it being too tight: there is nothing more irritating than having to dismantle a trellis to cut a few mm off the battens that are jamming!

If the space is regular you can cut all of the pieces you need. If it is irregular (e.g. if the posts you are fitting them between are not quite parallel) consider cutting the outside battens only (top, bottom, left and right); You can assemble these and check they fit before cutting the ones that go in-between.

3. Assembling the Trellis

I created two jigs (see above) — one for each end of the panel — into which the long horizontal slats fitted, ensuring I maintained consistent spacing. The jig was made from an offcuts of tile batten (blue), ensuring that there was enough space to slip the shorter vertical slats beneath. A piece of 2 x 4 acted as a stop allowing me to get all the long slats in line.

I used narrow (4mm) stainless steel screws to fix the slats at every junction. Using narrow screws meant that pre-drilling was not essential, although I did drill pilot holes at the ends to prevent splitting. On other trellis projects I have used nails, but they are a pain to get out if you make a mistake.

Example of horizontal trellis panels I constructed to increase the height of a fence in my black and white garden.

4. Fixing the Panels Between Posts

The two vertical end battens were drilled and 3in (75mm) decking screws driven partly through. The panels could then be offered up, clamped in place and the screws driven in.

More privacy?

If you need more privacy then a second set of horizontal battens can be screwed to the rear of the panel visually filling the gap, whilst allowing air to circulate through the structure.

Up close you can see the additional slats fixed to the rear of the panel. From this unusual angle you can just get glimpses through the structure, but from most normal viewing angles the trellis effectively blocks the view as you can see in the photo below.


24 thoughts on “How to make trellis panels”

  1. I was adamant that I was going to make trellis for our fence as shop bought is not the right size and I’m determined to save money. I didn’t, however, have a clue where to start!

    This article has everything I need to start this project. It’s comprehensive, easy to understand and gave me information I didn’t know I needed! (For example, the impact of spacing on wind speed).

    Really appreciate the information, thank you 👍

    Reply
  2. Read your page and found it helpful. But needed to know how to find out how much batten ( 38×25 ) is needed in a 6’x 5′ panel with 4″ squares. Not sure if can help,if you can it would be very much appreciated.

    Reply
    • I assume your 4in squares include the baton (So each “hole” is 4in – 38mm) in which case you will need 3 batons per foot plus one to finish off.

      > 6ft lengths of 38×25……… 16 off
      > 5ft lengths of 38×25………19 off

      Hope that helps.

      Reply
    • In theory, yes, as 4.8m lengths are just under 16ft.

      A long panel like that would be very unwieldy and would need a central post to support it (think wind if nothing else!). I would recommend getting a strong central post and making two shorter panels if I were you.

      Reply
  3. Thanks for that,but I’m thinking of fixing the bottom half of the panel directly to a block wall ( running 3×1 lengths of timber (3of) ) lengthways with the top half free standing. ???

    Reply
    • Sounds fine. Hope it goes well!

      (When I’m building anything and can foresee a potential issue, I try to think though a plan B, such as how or where I might add a support bracket if it proves necessary. Most of the time it’s not needed, but when it is I’m really pleased I’m ready and prepared!)

      Reply
  4. 16′ panels, I have done 2 very easily at the end of a garden. Both had decorative bow tops (Flash not necessary but they added rigidity (Plan “B”) ).

    They were on top of 3 – 6’x6′ Arris rail feather edge panels (two panels cut down to to length).
    Yes I use screws 3.5 x 30mm + No6 (3,5mm screw cups) screw cups. pilot drill all end holes (and the rest if I feel the need. Adding screw cups help to prevent splitting by giving a wider fixing area

    Very informative article thank you.

    Reply
  5. Hi, It’s a great article.
    I know it’s a lot more complicated, but have you ever tried making diagonal trellis? if so have you done a tutorial?
    Also, using roof battens rather than tanalised (pressure treated) timber, are the roof battens treated with anything or does the paint do that job.
    Thanks
    Les

    Reply
    • Hi Les, No, I’ve never made diagonal trellis – as you say, it’s quite a bit more tricky!

      Roof battens are tantalised. They are usually treated to UC2 – suitable for occasional wetting (as you might expect under roof tiles). In the garden they provide 10 to 20 years service where they are clear of the ground and can dry out easily after rain. Painting (or as I prefer, staining) will increase their longevity dramatically. On my garden buildings (which also have gutters) stained tile battens used as trims (e.g. around windows) have shown zero visible deterioration in nearly 20 years!

      If you let plants grow densely over them – e.g. ivy – the increased humidity is likely to reduce their service life.

      Reply
  6. Hi
    Just what I was after. I’m making a free standing trellis higher than my stepped garden wall (on a slope. 6′ high). Plan to level of screen so posts at one end would be 7′. I’m think of just having trellis for top half of posts. Do you think I’d need to brace posts with a rail half way up? Plan to grow clematis, honeysuckle and the like.

    Reply
    • Hi Mike – Sounds like a project! I’m not sure what you mean by a brace half way up. Do you mean under the trellis, like a rail? If I get your drift, the bottom half of each panel is open, so you are creating a trellis run only along the top half of your ‘fence’. If so, then Yes, I would run a rail across the middle for the trellis to sit on, otherwise it will sag over time. You might want to put a similar dimension cap above the trellis. If you do this, you could use long timber spanning several posts. That will help lock them all together and make a stronger run.

      Reply
  7. This is such a great post! I am now ready to build my trellis fence, you did all the work for me and I am so great full! I really had no idea how to begin so I was just going to wing it but not now. Our current fence is partly falling down and I determined to build it myself so I can get the look I want without the price. Thank you!

    Reply
  8. Excellent tutorial. I have concrete posts in my garden. Any idea how to attach the trellis to them? I’ve found extender posts but there would still be a gap above the concrete post if I used these.
    Thank you

    Reply
    • Hi Amy, thanks for the upvote. I extended a 5ft fence with concrete posts by screwing 2”x4” treated timber to the front of the concrete posts. These extended an additional 15” higher than the posts. I then added an extra piece of 2×4 to the back of the top section, creating effectively a 4×4” extension post. I then screwed trellis panels to the back of these, which placed the trellis directly above the wooden panels. Perhaps this could work for you?

      Reply
  9. Thanks for the info. I’m getting ready to start making 6’ x 8’ fence panels for our backyard by ripping pressure treated lumber.

    I can’t decide between paint or stain, but I’m curious about the upkeep in future years. How does one restain or repaint an entire lattice fence?

    Reply
    • Thanks for stopping by. I hope your project goes well.

      Personally, I’d avoid any kind of paint and go for an oil-based stain every time. Paint will eventually crack and peel and it will be all but impossible to rub down later. My preferred wood treatment are the OSMO One Coat range, or Barrettine Premier Wood Preserver. They are super-easy to apply and do not crack or peel. Over time, they gradually erode (thin), but it is easy to apply a new coat on top – no sanding needed. Obviously, trellis is always awkward to get a brush into all of the surfaces, but with these stains, even if you only go over the easy-to-reach parts it will spruce it up without looking too patchy. Hope that helps!

      Reply

Leave a Comment

%d bloggers like this: