How to build a Besser block bench seat

[Peggers]

Difficulty: Beginner

Besser blocks are a versatile building material that look terrific. They can be great for affordable D.I.Y. furniture designs.

This Besser block outdoor bench is an easy project that can be completed in an afternoon with just a few materials.

Many thanks to experienced Workshop member @sandy_d for the inspiration for this very popular project and for supplying images of her process.

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Steps

Step 1

Use a wide paintbrush to paint the Besser blocks. Using your construction adhesive, secure three blocks on top of each other in a horizontal position. Expose only the holes in the top block. Repeat this to create four separate sets of three blocks. Use cement filler to fill the gap between blocks.

Step 2

Sand the timber well for a smooth finish and apply varnish.

Step 3

Move the blocks to their final position. Use your construction adhesive to glue two sets together for one side of the bench and repeat for the other side. Glue a single block in a vertical position on top of the back set on both sides for the backrest.

Step 4

Insert the timber pieces into the slots of the Besser blocks. Add cushions to style your outdoor bench.

  

Materials

• 390mm x 190mm x 190mm Besser blocks x 14

• 100mm x 100mm sawn Pine posts x 6

• 1L timber varnish

• 1L exterior paint

• Construction adhesive, such as Selleys Liquid Nails.

Tools

• Orbital sander with 80-grit sander sheets

• Tape measure

• 50mm paintbrush.

Images

        

[DIYorDYE]

Thanks, I love this idea! 
just a question. Will the backrest be sturdy enough without support behind it or does it need to stand against a wall to be safe?

cheers

[MitchellMc]

Hi @DIYorDYE,

Let me mention @sandy_d to see if she can answer your question about her project. The adhesive used is very strong, and the blocks have a hefty weight to them. If the bench is not being placed against a wall, I'd advise the additional step of glueing the two upright columns of blocks together. In step three, glue blocks one, two, and three to blocks four, five, and six. This would create one solid structure and will be very sturdy.

Mitchell

[sandy_d]

Hi @DIYorDYE 

As @MitchellMc has suggested, if you’re not using a support behind the bench, it would be best to glue the blocks all together to make it one piece. You’ll be surprised how strong it is. There would be no change of tipping over once all blocks are glued together. Just ensure you have a level ground. 

Feel free to ask if you have any other questions 😊

[cheriewallace]

I can't wait to build this! I have a couple of questions though.

1. I'm assuming it would be easy enough to shorten the timber and make chairs as well?

2. Could additional block be added at the front to make a daybed?

3. Is the timber glued to the blocks, or just sitting in place?

[EricL]

Hello @cheriewallace

Welcome to the Bunnings Workshop community. Thank you for joining the discussion.

Let me tag @Peggers to make them aware of your kind words and questions. Based on the construction of the seats it is possible to shorten the timber to make chairs. Turning it into a daybed is definitely possible, just make sure that the Besser blocks are glued together very well. To make sure the timber does not slide out, I suggest putting adhesive on the wood so that it stays in place.

It sounds like a very interesting project. Please make sure to post an update on your bench seat project. I'm sure our members would be keen to see what your layout looks like.

Eric

[Winnie20]

Love to do this.  Does the base need to be concreted in or is it heavy enough to just sit on level ground?

[EricL]

Hello @Winnie20

Welcome to the Bunnings Workshop community. Thank you for joining the discussion.

That is an excellent question, I was under the impression that the Besser blocks along with the timber would be heavy enough to hold everything in place. Let me tag @Peggers to make them aware of your kind comments and question. Just to be safe. I recommend putting adhesive at the bottom of the Besser Block bricks to make sure they don't topple over when heavy weight is applied.

If you need further assistance, please let us know.

Eric

[lakiita]

Hiya,

I'm planning to make this bench and was wondering what colour stain you have used as I really like the colour it has turned out. I have been using a lot of Walnut stain lately buy my results end up very uneven. Look forward to your advise on this.

[EricL]

Hello @lakiita 

Welcome to the Bunnings Workshop community. Thank you for joining the discussion.

It's fantastic that this project has inspired you to build your own Besser block bench seat. Let me tag @Peggers to make sure they are made aware of your question. There are quite a few timber varnishes and stains to choose from, but if you are after a light protective coating, I suggest looking at the "Natural" finishes. Just remember to let your timber pieces season for a few weeks before you paint them.

Please keep us updated with your progress, we look forward to seeing the bench seat assembled.

Eric 

[Jason]

The photos here are actually from @sandy_d. Let me tag her to see if she can share what she used on the timber in her popular project. 

Jason

[lakiita]

EricL

what do you mean by letting the timber season? I recently attempted to stain my front door and it's been a disaster but a previous table I did turned out brilliant - I really want to make this bench work so I need all the tips I can get!!!

[sandy_d]

Hi @lakiita 

I hope you are well. I also used a stain in walnut and recently used the Sikkens range for my outdoor seat to protect it further. The product is here Sikkens 

Some parts of the posts may absorb the stain darker than other parts. The way I combatted this is to apply the stain to a lint free rag ( I used an old cotton T Shirt) and have another rag dipped into turps. This will change depending if your stain is water based or oil. 
I stained one face at a time, making sure I didn’t overlap the stain by using long sweeping motions. If I did have an area that absorbed too much stain and was uneven, I used circular motions to even it out and the turps rag to thin out the stain a little. 
If you had an off cut of timber, you could practice and get the right consistency. 

I hope I helped answer some of your questions.

Sandy 

[EricL]

Hello @lakiita 

Freshly treated timber will sometimes have oil and tannin still coming out of the timber. Seasoning means giving the oils and tannins time to wash out of the timber. You can shorten the waiting time by washing it with Intergrain 1L UltraPrep Tannin And Oil Remover. Just keep in mind that if the surface of the timber looks neat and dry, give it a few days out in the open to see if any of the oils or tannins begin to leach out. 

If you need further assistance, please let us know.

Eric

[lakiita]

Oh wow never knew any of this stuff. Thanks so much everyone for being so willing to share your knowledge. So up until now when staining timber I have just used a paintbrush - am I better off using cloth???

[MitchellMc]

There's a good chance you'll have a more consistent finish with a cloth @lakiita. Paint brushes work well if you are saturating the timber with stain and sending it a dark colour. However, for lighter stains, it's very hard to only partially load up the paintbrush for thinner coats. With the rag, you can wipe over an area without depositing so much stain that it saturates the timber. It might take you more coats with the rag, but you'll have a higher degree of accuracy.

Please let me know if you have further questions.

Mitchell

[lakiita]

What type of cloth is best? The big bags of white cloth that you can get at Bunnings are they good for it?

[MitchellMc]

Those should be fine, @lakita. Select a rag that doesn't release a heap of lint or fibres.

Mitchell

[lakiita]

My materials have arrived YAY - unfortunately I also ordered a BBQ and promptly cut my hand open trying to assemble it - 1 ED visit and 7 stitches later I still can't get the bbq done and I can't work for a week. Not the most auspicious beginning however I am determined to nail my patio reno.

So back to the besser block bench - I got the recommended treated wood planks - but they're pretty rough and I'd like to sand them - does this then damage the 'treatment'

[EricL]

Hello @lakiita 

I'm sorry to hear you got injured while assembling your barbeque. In regards to your timber planks, I suggest wearing proper safety equipment such as gloves, goggles and a heavy-duty dust mask before you start sanding the panel. make sure that no one is around while you are sanding to prevent them from being exposed to the saw dust. Sanding the surface of the panel will not damage the treatment. 

My number one tip is to keep the timber panels inside your garage. This will keep them safe from the weather and prevent them from twisting and warping. I also suggest painting or sealing them as soon as possible to prevent them from drying up. 

Please keep us updated with your progress, we look forward to seeing your bench seat assembled.

Please stay safe and get well soon.

Eric

[lakiita]

yes the planks are in my garage for protection. I will try to start sanding them tmrw depending on my hand. The BBQ is assembled but I have to do things in shifts due to injury - slowly getting there though Thanks for the encouragement everyone!!

[lakiita]

The project has begun - how do I know when the planks are sanded enough? Do I go on looks or feel? So far,  I have just sanded with 40 grit but also have some 80 grit to finish if required. I am confused by some charcoal looking black marks on the wood - unsure if I need to sand until these are gone or if this is part of the wood grain and will look fine when stained ie just end up slightly darker brown patches?

Sanded planks are the three on the left what are the black streaks? Do I sand until they're gone for a good result?

[MitchellMc]

Hi @lakiita,

The black streaks running across the timber appear to be milling marks below the timber's surface, and sanding them out will be difficult if they are quite deep. The other dark patches are likely just discolouration of the timber. @sandy_d had similar marks on her timber, which don't appear noticeable after staining. Some of the marks might remain visible depending on the darkness of the stain you're using. 

I'd advise doing a test section with your choice of stain to see whether further sanding is required. Please remember your PPE when sanding timber and staining, including a face mask, gloves and safety glasses.

Please let me know if you have any questions.

Mitchell

[lakiita]

Thanks that's super helpful - as you can tell I am an absolute DIY beginner - I have 3 studd finders and still can't figure out how to hang things. 7 planks down (I'm making 2 benches) but have had to take a break due to my hand. Next drama is trying to figure out a setup where I can paint things without getting paw prints from the furkids on them - Thinking of doing all staining and painting in the cattery (very large but spoiled cats decided they preferred my patio and were super vocal about it) I have a trestle table I should be able to set up in there and have kept the boxes from my recent bunnings delivery - wish me luck!!

[EricL]

Hi @lakiita 

Any chance you can leave the car outside for a day or two and paint in the garage? I hope you find a painting spot safe from the pets.

Eric

[lakiita]

Great idea re garage except my garage is more a covered carport with two sides without walls and I haven't been able to afford to enclose it yet so unfortunately it won't keep the furkids away. I can't even use it for my car as the dogs can run out if I opened the door to put the car in. It's on my to-do list to figure out how to enclose it. I do have a garage in my back yard but also not furkid safe as the walls don't meet the floor (also on the to do list - might make a besser block barrier   ) Also it would be CRAZY hot and the cattery won't be. Good motivation to give the cattery a big spring clean prior to setting up for painting. 

[lakiita]

Ok so in the end when I realised how quickly the stain is touch dry I decided to set up in my patio. Two coats in of these 4 and it's looking great. Using a cloth and a cloth of turps is a great idea - it gives such a lovely smooth result. Now just wondering (as my patio occasionally gets rain) if the wood needs some kind of outdoor gloss type protection as a final layer? Excuse the mess

[EricL]

Hello @lakiita 

Can you please post a photo of the paint can you're using. I just need to be sure of the product you're using so that I can make the proper recommendation for a sealer. It's important that the products are compatible otherwise they might not work together.

Eric

[lakiita]

Hi Eric,

Thanks for continuing to be so helpful ok here's the stain that I'm using 

[EricL]

Hello @lakiita 

Thank you for posting that photo of the oil sealer. Technically, the Cetol HLSE by itself is more than enough to protect the timber, you could for example use Sikkens 1L Cetol TGL Gloss Plus Clear Timber Finish, unfortunately it is not suitable to be used for steps or seating. The same goes for the Cetol Filter 7 Plus, it is an excellent added sealer, but again not suitable for steps or seating.

I don't recommend mixing and matching products from different manufacturers as you don't know what kind of reaction you will get. 

For extra protection, I suggest adding an extra coat of Cetol HLSE on top of your current finish. The more coats you put on the timber the more protection you will get. Just remember to give the oil enough time to cure before putting on the next coat.

Please make sure to wear proper protection such as gloves, goggles and a paint mask while oiling your timber pieces.

If you need further assistance, please let us know.

Eric

[lakiita]

Thanks Eric,

I have been following the instructions and leaving 24 hours between coats. Maybe I will put on 4 coats instead of just 3 then but then I don't want the timber to get so dark that you no longer see the grain of the wood.

Or could I use something like this? https://www.bunnings.com.au/cabot-s-500ml-gloss-exterior-clear-timber-finish_p1521728?store=8182&gcl... 

I could do a test patch leave it for 24 hours and see what happens? It mentions here that it can be used on stained products provided they have dried. What reaction would you be worried about from mixing products and how do I know if it's suited to seating or not?

[MitchellMc]

Hi @lakiita,

There is no need to add a gloss coating over the Cetol HLSE, so any benefit of one is outweighed by the chance that it might not be compatible. There are typically two choices for coating exterior timber, either oil or varnish. The Cetol HLSE is an oil-based stain, and the oil content is what protects the timber. It's the same thing as we commonly oil decks; there's no need to varnish them with a gloss coat as well. The benefit of the oil is that it's very easy to apply maintenance coats periodically, but once a varnish deteriorates, you can be left with no other option than to sand back to timber and re-coat. Oil coats fade away over time and can be replenished. Varnishes tend to crack and discolour, and the compromised varnish must be sanded off before applying a new coat.

I'm keen to hear more about why you'd like to apply the gloss coat.

Please let me know if you have any questions.

Mitchell

[lakiita]

I think it's just because I don't know enough about wood. I don't know if I've used this type of stain before - previous wood projects I have used have ended up with a partially glossy finish so I think I equate that gloss with waterproofing. This is a much more matt look and so to me it doesn't look water protected and my patio can get heavy rain when the rain comes in sideways although I will admit that it will rarely reach where I am planning to have the benches set up.

[MitchellMc]

I can appreciate that, @lakiita. A glossy varnish is like a plastic bag over the timber; no water can penetrate inside it. That's its action of protection, to prevent water from accessing the timber. Oil works by filling the pores and fibres of timber to prevent the water from penetrating. They work on a similar principle, but one sits upon the timber, and the other penetrates into it.

We've used oil and petroleum-based products to treat timber for at least 70,000 years. Timber oiled periodically can last for hundreds of years exposed to the elements.

I recommend oil for anything other than a front door or trimming work around windows. In my opinion, something like outdoor furniture should always be oiled instead of varnished. I've assisted countless people with restoring varnished timber where the coating has degraded to the point that they need to fully sand the varnish off back to raw timber before re-coating. It can be a truly laborious process. Oil typically just fades and needs a re-coat. In the worst cases and quick sand is required to knock down any splinters or rough timber sections.

Rest assured, your 3-4 coats of oil will sufficiently protect the surface. You've also used a very good product that performs better than the more budget-friendly options.

Mitchell

[lakiita]

Awesome @MitchellMc  (finally figured out how to hyperlink lol ) thanks for that reassurance - that makes sense too as I can tell that the oil is sinking in to the wood by the colour changes I'm observing. It's quite beautiful watching the timber emerge and also easy for avoiding furkid pawprints as it doesn't remain wet on the surface for long. win, win - though luckily so far the furkids remain stunningly uninterested except for my dog who tried to eat my bunnings bag of white rags lol.!!!  

[lakiita]

Ok stupid question - I'm doing everything with gloves on and my hands still smell like timber oil - how do I get rid of the smell?

[EricL]

Hello @lakiita 

One way to wash off the smell of timber oil is to wash in very warm water mixed with dish washing soap and laundry detergent. However, if this is too strong for your skin one other method is to use vinegar. Wash your hands in vinegar and then wash off with soap and water. Unfortunately, timber oil is tough and difficult to remove. In both instances, please make sure to use moisturize your skin.

If you have any other questions we can help with, please let us know.

Eric

[Arameen]

what is the approximate cost of all the materials required for the Besser block and timber outdoor seating?

[MitchellMc]

Welcome to the Bunnings Workshop community @Arameen. It's terrific to have you join us and many thanks for your question on this fabulous project.

You'd be looking at around $60 a litre of exterior varnish, $144 for the six posts, $55 for the 14 Besser blocks, $40 for a litre of exterior paint and $5 for the construction adhesive. The total is around $300.

Please let me know if you have further questions or need assistance with the project.

Mitchell

[lockers]

@Peggers @MitchellMc @EricL 

Hope one of you can help with this.  Firstly awesome design and great directions.  I want to build a couple of these and now have the how to so I can start, my question is I want to place them on our Merbau Deck and wanted to see what I should place underneath each end to protect the deck.

[EricL]

Hi @lockers 

A few ideas come to mind. First, I suggest using Merbau off cuts under the Besser block. I recommend attaching them with liquid nails to prevent them from sliding off. The second one I suggest is using a Swing Slide Climb 1 x 1m x 20mm Shock Pad Rubber Paver. You can cut them into strips the same size as the Besser blocks. This will protect the Merbau surface and is designed for outdoor use. 

My third suggestion is to use Surface Gard 41mm Brown Square Rubber Base Castor Cup - 4 Pack. You can glue these rubber pads to the corners of the Besser blocks to serve as feet for the bench seat. 

Let me call on our experienced members @Dave-1 and @TedBear for their recommendations.

If you have any other questions we can help with, please let us know.

Eric

[Dave-1]

Good Evening @lockers 

Any chance you can supply a photo of your deck? I am just thinking of the overall weight of bessa blocks sitting on an unsupport span on someones deck (the bit that is between two screwed/nailed down sections. Is the deck covered (think of a rain soaked bessa block) I like the idea of the rubber brick that eric is talking about or even gluing some offcuts of merabu timber to the base of the blocks. 

I was a little dubious when I fist saw the seat project but it really sounds like gluing the bessa blocks together works. Are you intending to move the seats around on the deck or will they be once buit they are staying put? Mmmm I have some cap stones for bessa blocks, I might have a go at testing the strength

This is the first thing that come to mind about protecting your deck ultimate flooring 1200 x 800 x 5mm rubber ute mat and cutting into strips to fit under the bessa blocks, or you could use even old door rubber mats

Dave

[lockers]

@EricL thanks for the ideas, will go check them out once I start the build.

@Dave-1 Deck is on the adjustable footings just off the ground and when we initially built it, it was covered in treated pine, due to the length of the boards I halved the recommended distance.  The joist are about 30cm apart so there is a pretty good chance the besser blocks will sitting on top of a joist.  I didn't consider the cover first up as I just wanted to get something on the deck so we can actually use it.  To finish off the blocks I was considering using the render effect paint.  Would that help to protect it against the elements?

[EricL]

Hi @lockers 

Any coating applied to the blocks is like a first line of defence. It will definitely help protect it from the elements. Even just by using outdoor paint on the blocks will protect it from getting mould and mildew in its pores. I agree with you in using render effect paint on the surface of the block.

If you need further assistance, please let me know.

Eric

[Dave-1]

Morning @lockers 

Nice spacing with the joists And yeah there is a fair chance the blocks will be sitting on one plus a lot less flex if it isnt.

Coating the block would look nice but I have not had any experience in doing something like that. I need to learn as I have some areas along my retaining wall that need to be repaired but can offer no advice about how to

Dave

[sara22au]

So this is my learned something new today! I'm a big fan of bessa blocks, the versatility is endless, but I never thought of using a construction adhesive to join them! I usually use cement/concrete or morter, so this is something really useful to know, thx😁

[Zengarden]

Hi, do the Bessel blocks have to be glued together to make the seat. I am in a rental so when I move I would like to take the seat with me. 
thanks

[fjamieson]

I am very excited by the design and all the information you have given for the construction of this seat. Any thoughts on if there would be a problem if you added an extra block at each end to form arms for the bench - something to rest a cushion against?

[MitchellMc]

Welcome to the Bunnings Workshop community @Zengarden. I do apologise as we seem to have overlooked your comment.

It would be best to glue the blocks together for safety reasons. Although you could build the seat without adhesive and it would hold together, our concern and reason for glueing is mainly to prevent a child from pulling a block off and onto themselves. However, it does also add rigidity to the whole structure.

Please let me know if you have any questions.

Mitchell

[JacobZ]

Hi @fjamieson,

A warm welcome to the Bunnings Workshop community, it is fantastic to have you with us.

I can't see any reason why adding another block to create arms that you can rest a cushion against would be an issue as long as the block is firmly on top of the other blocks and glued in place.
 

Allow me to tag @Peggers so they are notified of your question. Hopefully, he will respond soon.
 

If you have any further questions, please don't hesitate to ask.

Jacob

[Whatho]

This project is perfik for my courtyard. Thank you.

[EricL]

Hello @Whatho 

Welcome to the Bunnings Workshop community. It's sensational to have you join us.

I'm sure @Peggers will be happy to hear that their project has inspired you to build your own bench seat. 

We're keen to hear more about all your projects and plans around the house and garden. Please feel free to reach out whenever you need assistance or would like to share project with the community. 

If you need further assistance, please let us know.

Eric