FREQUENTLY ASKED QUESTIONS (FAQ)
From TuffBlock's installation guide to our Shipping Policy, this FAQ will help you find the information you need.
Warranty: Tuffblock won't chip, crack, corrode or grow mold like traditional concrete blocks. We're so confident in the TuffBlock, we give you a 25 year manufacturers warranty from the date of purchase.
For more on our warranty policy, please click here.
Questions that are answered in this TuffBlock FAQ video:
0:00 What is a floating foundation system?
0:31 How much weight can each TuffBlock support?
0:43 Are TuffBlocks UV resistant?
0:58 Can I use TuffBlocks on sloping ground?
1:14 Do I need council approval?
1:34 How do posts/joists sit in the TuffBlock and do they require fixing?
1:56 Can TuffBlocks be used on wet surfaces?
2:22 Can I use TuffBlocks on sand?
2:35 Will TuffBlocks sink into the ground?
3:08 Can I use TuffBlocks in high wind areas?
3:27 How many TuffBlocks will I need for my project?
3:57 What if I have ground movement in my area?
Please note. This FAQ video relates to both the TuffBlock and Evo-Crete Handi Block products. BuildTuff offers this information as a general guide only. You should rely only on relevant building codes and standard industry established construction methods in any construction project.
TuffBlock is an ultra-light weight and versatile footing made from 100% recycled materials. TuffBlocks can be used as a footing for a number of projects including low-profile and slightly raised decks, patios, sheds, landings, walkways, cubby houses, dog sheds and more.
Deck blocks were introduced over 30 years ago in the USA and since then, instant foundation blocks have been embraced worldwide for creating strong and stable foundations for both professional and DIY enthusiasts. TuffBlock's are an extremely popular alternative to digging holes, carrying heavy concrete blocks, mixing concrete and waiting for it to set. TuffBlock's are a versatile utility block and the options are endless for how you can use them to make completing your projects a breeze.
The floating foundation system has been a tried and trusted building system in North America since the late 1980s with literally tens of millions of decks being built using the system. In fact, the floating foundation system was developed for grounds that were heavily affected by freeze and thaw. If your grounds are particularly unstable, the floating foundation system such as TuffBlock is possibly a far better solution for you to use. It also keeps your structure independent from any surrounding fixed structure, allowing it to move and settle independently.
TuffBlocks are made of high strength, closed loop recycled plastic. The plastic used to create our TuffBlocks is sourced from the ocean. The great thing about this is that TuffBlocks are designed to last decades, which means they can be recycled again in future.
Made in America for professionals and home improvement renovators. Each TuffBlock is incredibly strong, with its vertical load designed so that an individual TuffBlock can support 1,700lbs (770kg). TuffBlock's have also been break tested to 11,000lbs (5,000kg).
TuffBlocks have been engineered to be stackable and only weigh 1.5 lbs each, compared to that of a traditional concrete deck block that weighs 41.5 lbs each!
TuffBlocks can be used for a number of outdoor projects. Whatever you do, make sure to use your TuffBlocks on level and compact ground. The TuffBlocks will be the foundation of your build. Build ideas include decks (low profile, raised and floating decks), garden sheds, landings, pathways, raised walkways, cubby houses, dog shelters and more.
TuffBlocks should be installed on a stable, undisturbed grade surface, with well-draining sub grade material. If your soil is constantly wet and gets flooded, you would need to ensure that you prepare the ground by introducing drainage which can be done via gravel or additional drainage to remove the flooding. If the ground is particularly unstable, we would recommend increasing the number of TuffBlocks supporting your structure.
Yes, simply level the ground under each TuffBlock. Then level the structure above using extension posts supported by the pocket of the TuffBlock below. Refer to the installation guide for more detail. Essentially, if the surface is concrete or similar and the surface on which the TuffBlock will sit cannot be levelled, the base of the TuffBlock can be cut off at a suitable angle. Alternatively, if the impenetrable surface is sloping at a severe angle, it may be worth considering using an alternative support/footing/foundation.
Yes. Use them on concrete, soil, gravel and everything in between so long as it meets the “stable ground” criteria. TuffBlocks can be used on any substrate which would be an acceptable base for concrete-in-ground footings. If the ground is not compact, just clear away a few layers until you find compact earth.
Yes, you can use TuffBlocks in high wind areas (Cyclones, Hurricanes, Storms etc), but we recommend checking in with your local building authority first. Some TuffBlock users choose to use the intermediary solution in high wind areas, which means they use TuffBlocks in combination with concrete in ground footings to tie their project down.
You cannot anchor down an individual TuffBlock, but you can anchor down the entire structure with a single point in the middle or at each corner. Some methods include concreting down steel chain into a hole or you can use earth anchors which you can hammer down into the ground.
Yes. Especially when you consider the time and effort taken to dig multiple holes and then mix the concrete to fill them back in, not to mention the cost of buying the steel post supports and bags of concrete in the first place. Generally a steel post support and two bags of concrete will set you back around $24-30 USD. Even if you use a few more TuffBlocks, you are still well ahead of the old conventional footing method.
Generally the post-joist bearers sit in the TuffBlock without requiring any fixing. If fixing is required, fix the block to the timber. As for the post staying upright; this is a function of the deck build itself. Your structures should be adequately designed and reinforced to ensure the posts are structurally sound and cross braced.
Posts: Accepts 3.5" x 3.5" or 4" x 4" Posts
Joists & Bearers: Accepts 1½ - 2" Joists & Bearers
UV stabilisers have been included in the manufacturing process which means TuffBlock is manufactured to the highest standard of any plastic product for outdoor use. That’s why we back it with a 25 year warranty.
It is completely dependent on the project but we recommend using our TuffBlock Calculator found on our product page. As a general rule, if you are supporting joists directly on TuffBlocks, you will need to support joists with a TuffBlock at 4' 11" intervals. Joists will need to be spaced at a distance appropriate to the finishing material (e.g. it is recommended that some decking lumber be spaced at 17" centres, it is always best to check with your lumber/material supplier for material specific recommendations).
As an example, a low level deck 10 x 10 feet would require 21 TuffBlocks for the above configuration – that is 3 x TuffBlocks per 10 foot joist, 7 x joists spaced 17" apart.
If you intend on using bearers on top of TuffBlocks, joists on top of bearers, and then decking or finishing material/sheeting – less TuffBlocks will be required. As an example, a low level 10 x 10 feet deck would require bearers to be supported say every 4' 11", bearers would be spaced every 4' 11" to support the joists, so 3 x TuffBlocks per bearer. 3 x bearers = 9 x TuffBlocks. The above measurements are a basic guide only. Please refer to the TuffBlock installation guide and your material supplier to ensure correct spacing is maintained for structural integrity.
The TuffBlock product is based on the floating foundation system, designed to ensure the structure is able to move slightly if the ground was to move. This is what makes the floating foundation system so safe. The structure is able to move slightly and independently of other structures as natural ground movement occurs. The TuffBlock construction method therefore avoids stresses that would otherwise see an extension from an existing structure fail. The system was originally designed for regions where the annual freezing and thawing of the ground meant that either: 1) the ground was too hard to dig, or 2) with the constant shrinking, expansion, and movement of the ground many fixed structures failed due to inability to cope with the movement they sustained.
This is exactly where the Floating Foundation System was developed for areas in the north (USA) where freeze and thaw ground movement is a major issue for traditional "dig a hole and pour concrete" structures. So TuffBlock is a perfect solution for their application.
No. As TuffBlocks support the structure well above the soil line and the blocks themselves wick moisture away from the lumber, there is no reason for the lumber to rot or for termites to attack the posts.
Plan and understand your project and seek professional advice if needed. BuildTuff strongly suggests you make your own enquiries through appropriate bodies and professionals before any work is carried out. Some questions you may need to address are:
- Is the site going to need protection from wood boring insects?
- Has the deck got potential for water pooling or constant exposure to water?
- Is there a need to install drainage due to potential soil erosion?
- Are there any trees growing near the project whose roots could upset foundations or branches create a hazard?
- Are you building on solid ground (Eg. not reactive soil)?
- Will you need electricity, gas, water or other services to your project in the foreseeable future?
- Are there any height considerations (Eg. Fencing, balustrade and handrail needed to comply with codes)?
- Do you need an engineer to specify and detail construction drawings and methodology?
- Are there fire regulations I need to follow?
You may need approval depending on size, structure and height. Your local county or authority may also have certain building rules and regulations. Contact your local county to confirm requirements, regulations and permitted sizes. If in a fire prone area, you may need to factor in specific requirements to meet regulations. As building guidelines change from shire to shire, we always recommend checking your local guidelines before commencing construction, we always suggest you get the thumbs up before starting your project. Unfortunately there is no single or “golden rule” answer. That being said, most countries have an exemption for structures that are less than a certain size (Eg.108 ft). Therefore, if your structure or deck area is less than specified, you may not need to seek any approvals.
You may need approval depending on size, structure, height and your local county or authority laws and regulations. Contact your local county to confirm requirements, regulations and permitted sizes. These vary by region. If in a fire prone area, you may need to factor in specific requirements to meet regulations.
An individual TuffBlock can support 770kg (1,700 lbs) and has been break tested to 5,000kg (11,000 lbs).
You can buy TuffBlocks right here on our website OR via our other retailers:
Online: TuffBlock is available to order online at Amazon USA / Amazon Canada / Lowes.
USA in-store: To purchase TuffBlock in-store, please use the Store Finder to search for your local store.
Canada in-store: To purchase TuffBlock in-store, please use the Store Finder to search for your local store.
Please note: BuildTuff.com offers this information as a general guide only. You should rely only on relevant building codes and standard industry established construction methods in any construction project.