FAQ
Adjustable Joist Support Frequently Asked Questions
What are the minimum and maximum top of joist/bottom of joist heights for the complete range of KlevaKlip Deck Building Products?
How to achieve Min & Max Top/Bottom of Joist heights PDF
How can I purchase the KlevaKlip Adjustable Joist Support?
Via your preferred Timber Merchant or Hardware store or alternatively you can purchase on our Online Store
How is the Product Purchased?
There are now three options available when purchasing the Adjustable Joist Support- either the Adjustable Joist Kit which includes Bolts, Nuts, Washers and Dynabolts or the Adjustable Joist where they are not included.
Option 1: Adjustable Joist "Kit" (AJ45KIT):
The product comes in boxes containing 16 joist supports,16 base plates, 32 x 100mm M10 hex bolts,64 x M10 hex nuts, 32 x M10 washers and 16 x 12mm dynabolts.
Option 2: Standard Adjustable Joist (AJH45G):
The product comes in boxes containing 24 joist supports and 24 base plates.(see photo below) Bolts, nuts, washers etc.are purchased separately from your hardware store/merchant depending on what height you want to achieve. Each Adjustable Joist Support ( joist holder + base plate) requires 2 x M10 Hex Head Bolts, 4 x M10 Nuts & 2 X M10 washers, 1 x 12mm x 50mm Galvanised 12mm dynabolt or x 10mm x 60mm masonry bolt or similar.
Option 3: Standard Adjustable Joist Support (AJH50G):
The product comes in boxes containing 24 joist supports and 24 base plates.(see photo below) Bolts, nuts, washers etc.are purchased separately from your hardware store/merchant depending on what height you want to achieve. Each Adjustable Joist Support ( joist holder + base plate) requires 2 x M10 Hex Head Bolts, 4 x M10 Nuts & 2 X M10 washers, 1 x 12mm x 50mm Galvanised 12mm dynabolt or x 10mm x 60mm masonry bolt or similar.
Differences between Adjustable Joist "Kit" (AJ45KIT)verses Standard Adjustable Joist Support (AJH45G)?
Advantages
- Easy sourcing – box contains everything you need to build your structure
- Fully threaded 100mm length bolts provide maximum sustainability to cope with your required height and any irregularities in your concrete
- Easy for the retailer – no special ordering or calculating of bolts etc, and no problems regarding thread length of stocked bolts
Disadvantages
- All Kit bolts supplied are 100 mm length – sometimes customers require 120mm length bolts then purchase AJH45G
- For top of joist height below 106mm, customers may need to cut off the portion of the bolt protruding above the joist (relevant for 70mm joists)
How is the AJ45KIT & AJH45G Adjustable Joist Support product packaged?
AJ45KIT- How Packaged in box AJH45G/AJH50G - How Packaged in box
16 Base Plates & Joist Supports 24 Base Plates & Joist Supports
Includes: Bolts, Nuts,Washers & dynabolts Excludes: Bolts, Nuts,Washers & dynabolts or masonry bolts
Which is the most economical way to purchase the Adjustable Joist Support – the AJH45G or the AK45KIT ?
All hardware stores sell their nuts and bolts at different prices, so we cannot be sure of what price you will pay. However the research that we have undertaken suggests that, as the nuts, bolts, anchors etc generally make up around 50% of the total costs, you are unlikely to come out “behind” by purchasing the AJ45KIT which includes all your nuts and bolts – unless of course you don’t need any nuts and bolts at all.
Minimum and Maximum "Top of Joist" Information for AJ45KIT,AJH45G and AJH50G Adjustable Joist Supports
Minimum top of joist heights
76 mm – fixing joist bracket direct to concrete no base-plate no bolts and using 70mm joist
86 mm – using Joist Support KIT- lowest height achievable using base-plate, 100mm fully treaded bolts and joist bracket with 70mm joist
86 mm – using Adjustable Joist Support AJH45G- lowest height achievable using base-plate, 60mm bolts and joist bracket with 70mm joist
106 mm – using Joist Support KIT- lowest height achievable using base-plate, 100mm fully threaded bolts and joist bracket with 90mm joist
106 mm – using Adjustable Joist Support AJH45G - lowest height achievable using base-plate, 60mm bolts and joist bracket with 90mm joist
116 mm – using Adjustable Joist Support AJH50G - lowest height achievable using base-plate, 60mm bolts and joist bracket with 100mm joist
Maximum top of joist heights
150 mm – using Joist Support KIT,100mm bolts & 90mm joist
170 mm – using Adjustable Joist Support AJH45G, 120mm bolts & 90mm joist
180 mm – using Adjustable Joist Support AJH50G, 120mm bolts & 100mm joist
180 mm – using Joist Support KIT, 100mm bolts & 120mm joist
200 mm – using Adjustable Joist Support AJH45G, 120mm bolts & 120mm joist
232 mm – using Adjustable Joist Support AJH50G, 120mm bolts & 150mm joist
200 mm – using Joist Support KIT, 100mm bolts & 140mm joist
220 mm – using Adjustable Joist Support AJH45G, 120mm bolts & 140mm joist
230 mm – using Adjustable Joist Support AJH50G, 120mm bolts & 150mm joist
Note – the above information is a “practical” rather than an “absolute” document. There will be a number of ways to achieve the heights mentioned with different sized joists, however the installer should always be mindful to operate within the KlevaKlip product parameters and relevant joist span tables
Can I use the Adjustable joist support with joists of greater than 90mm height?
Yes, the governing factor is either 45mm for the AJ45KIT/AJH45G or 50mm for the AJH50G in thickness, however there is no reason why the joists cannot be much greater than 90mm in height (eg, *120mm, *140mm or 150mm ).
* When using 120mm, 140mm or 150mm high joists 1200mm is the recommended and 1800mm is the maximum span for base plate positioning
Can I use the AJH45G Adjustable joist support with hardwood joists?
Yes, provided they are only 45mm wide. If your joist is 50mm use the AJH50G Adjustable Joist Support However, please note that you will most likely need to screw into the joists rather than using connector nails (and maybe even need to pre-drill).
Can I use the Adjustable joist support with steel joists?
Yes, generally you will find most steel joists are 50mm wide so use the AJH50G Adjustable Joist Support.
Can I use the joist support cradle without the base-plate and just fix this to my concrete?
Yes, the joist support component is designed to be able to be used on its own in areas that warrant this. The ribs in the bottom of the joist support will still keep the joist off the concrete by approx 6mm /15/64 inch. You do of course lose the "adjustable" aspect of the product.
Can I purchase the joist support cradle separate from the base plates?
No, the products come as a pair in boxes and cannot be purchased separate from each other.
What are the minimum and maximum length Hex Head bolts can I use?
AJ45KIT : Comes with 100mm Fully threaded bolts- if you need to go higher purchase the AJH45G and 120mm M10 hex head bolts from your Merchant or Hardware store.
AJH45G/AJH50G : Minimum 60mm Maximum 120mm galvanised Hex Head bolts.
Do I have to use the two washers for every adjustable joist support?
Yes, the washers are very important and form an integral part of the system.
What size galvanised dynabolt /masonry bolt or screw anchor should be used to hold down the base-plate?
AJH45G/AJH50G -1 x 12mm x 50mm Galvanised 12mm dynabolt or x 10mm x 50mm masonry bolt or similar. Note - if only using a 10mm dynabolt, you will need to use a washer under the nut to ensure you cover enough area of the base-plate.
What galvanising standards is the Adjustable joist support galvanised to ?
KlevaKlip Joist Supports and Base Plates have been hot dip galvanised in accordance with Australian Standards AS/NZS 4680:2006 (ISO 1461)
What is the Load bearing capacity of the Klevaklip Adjustable Joist Support?
This has been independently tested to support a load bearing capacity of 350kg per square metre when used at the recommended joist spans listed below. Engineers and Load Test Reports can be found at the following link: https://klevaklip.com.au/Technical-Information
What are the box dimensions and weighs of the Standard Adjustable Joist Support and the Adjustable Joist Support "Kit"?
Standard Adjustable Joist Support Weight 6.5 kgs Dimensions Length 26cm x 19cm Width x 17cm Height
Adjustable Joist Support "Kit" Weight 8 kgs Dimensions Length 35cm x 18cm Width x 12cm Height
Can I install the Adjustable joist supports over brick pavers?
No, this is not recommended as the pavers do not have adequate structural stability.
How to calculate how many Adjustable Joist Supports are needed for your deck?
We quite often find that people have miscalculated the number of adjustable joist support required for their decking area. We believe the main cause of this is that people work out the length of their joists, and simply divide by the "support spacings" (taken from our span table) they have decided on between the supports - eg - having a 3 metre length joist with spacings of 1 metre to give 3 supports.
Wrong! - This does not take into account the initial support at the start of the joist.
Therefore, the correct answer would be 4.
Similarly, when working out the number of joists required, you need to work out the number of "joists spacings" along your deck and remember to add one for the initial joist.
So, to finalise the number of supports you will need for your deck, multiply the number of joists on your deck by the number of supports to be placed along your joists. This should give you an accurate answer.
IF IN DOUBT - DRAW A SMALL DIAGRAM WITH CROSSES FOR YOUR SUPPORTS AS SHOWN BELOW AND SIMPLY COUNT THEM UP.
IN THIS EXAMPLE YOU WILL NEED 48 ADJUSTABLE JOIST SUPPORTS
Span requirements for base- plate positioning for AJ45KIT, AJH45G & AJH50G (Aus/NZ)
All based upon "continuous span" with joists at 450mm between centre's.
| Adjustable Joist Type | Joist Size | Recommended Span (mm) | Maximum Span (mm) |
|
Adjustable Joist "KIT" (AJ45KIT) Standard Adjustable Joist Support (AJH45G) |
70 x 45 MGP10 | 800 | 1200 |
| 90 x 45 MGP10 | 1000 | 1500 | |
| 90 x 45 MGP12 | 1200 | 1600 | |
| *120x45MGP10 | 1200 | 1800 | |
| *140x45MGP10 | 1200 | 1800 | |
|
Adjustable Joist Support (AJH50G) |
*100x50 Steel or Hardwood Joist |
1200 | 1800 |
|
* 150x50 Steel or Hardwood Joist |
1200 | 1800 |
* Joist span limited by lateral loading on bolts
"Heights achieved" when using 100mm for AJ45KIT, 60mm & 120mm long M10 Hex Head Bolts for AJH45G and AJH50G Adjustable Joist Supports (Aus/NZ)?
Note: All measurements for 60mm &120mm are based on using Galvanised Zenith brand M10 hex head long-threaded bolts.
| Adjustable Joist Type | Hex Head Bolt Length | Min Height to Bottom of Joist | Max Height to Bottom of Joist | Min Height to Top of 70/90 x 45mm Timber Joist | Min Height to Top of 100/150 x 50mm Steel or Hardwood Joist | Max Height to Top of 70/90/140 x 45mm Timber Joist | Max Height to Top of 100/150x 50mm Steel or Hardwood Joist |
|
Adjustable Joist "Kit" (AJ45KIT)
|
100mm | 16mm | 60mm | 86* / 106mm | 130 / 150 / 200mm | ||
|
Standard Adjustable Joist (AJH45G)
|
60mm | 16mm | 20mm | 86 / 106mm | 90 /110/160mm | ||
| 120mm | 18mm | 80mm | 88* / 108mm | 150 /170/ 220mm | |||
| **No Bolt | 6mm | 76 / 96mm | |||||
|
Adjustable Joist Support (AJH50G) |
60mm | 16mm | 20mm | 116/166mm | 120/170mm | ||
| 120mm | 18mm | 80mm | 118/168mm | 180/230mm | |||
| **No Bolt | 6mm | 106/156mm |
* If using long bolts at low heights, to prevent the bolts protruding past the top of joist, the end of the bolt will need to be cut off.
** When Using Joist Support Only.
What are the dimensions of the KlevaKlip Adjustable Joist Support AJH45G/AJH50G Base Plate & Support?
AJH45G AJH50G
