What are sleeve anchors?
Sleeve anchors are a quick, simple and adaptable masonry anchoring system. They are designed for application on a range of materials and for applications exposed to seismic loads. When the bolt of the fastener is tightened, it expands against the base material to create a strong connection and is able to distribute load-bearing weight.
Getting the right fixing for your project is crucial to ensuring its effectiveness and long life potential. Sleeve anchors are often permanent fixtures and choosing the right one for the job will increase your project potential.
In this guide, we’ll outline the different types of sleeve anchors, their application process and the most effective uses to help you choose the right fixing for you.
When to use sleeve anchors?
Sleeve anchors are versatile. They can be used for light or heavy-duty fastening so can be applied in projects such as fixing radiators in the home but also work for much larger operations such as securing the joists of decking.
These anchors can be used in a variety of base materials such as concrete, brick and block. The design of the fixings will determine where they can be used, with stainless steel sleeve anchors more suitable for outdoor, wet environments and zinc plated anchors for indoor, dry environments.
Stainless steel is anti-corrosive, even in marine environments, whereas zinc plating can rarely endure prolonged outdoor conditions. They’re well suited for interior use away from the elements.
There are various types of sleeve anchor (explained below) which means their uses become more diverse. Other uses for these fastenings also include connecting light fixtures to concrete walls or ceilings, attaching door frames and securing electric junction boxes.
(Sleeve Anchor S/S Loose Nut)
How to install sleeve anchors?
The strong bond between the fixing and the concrete is ensured by friction. This is why getting the installation of the sleeve anchor correct is crucial to the strength of the project.
Follow our installation guide to ensure a solid, secure bond every time.
Drilling the hole
First position the material you want to anchor and mark the locations of the product’s anchor holes on the concrete. If there is adequate clearance for drilling the holes, the product can be left in place. This allows for more precise positioning.
Next, use a hammer drill to drill the holes in the concrete at the product’s bolt hole location.
The size of the hole is crucial. The holes should be the specified diameter for the anchor that you plan to use and at least 1/2″ to 1” deeper than the expected depth of the fixing. Anchor lengths are measured from underneath the nut and washed to the tip.
To ensure proper hole depth, most hammer drills have a depth gauge. If not, wrap a piece of tape around the bit at the certified depth length.
Then clean the hole. This is such an important step before installing the sleeve anchor. It ensures proper installation and guarantees the anchor will have maximum holding ability. It will adhere directly the sides of the hole evenly rather than coming into contact with obstructing debris.
Attempt to remove all potential dust and debris with a wire brush, vacuum or compressed air tool.
Inserting the sleeve anchor
These fixings are pre-assembled. When inserting the anchor, position the nut so it is even with the top of the thread. This makes sure the threads are not damaged when installing.
Hold the nut and insert the anchor body through the products hole and into the base material.
Tap the anchor with a hammer until the nut and washer are flush with the fixing.
Hand tighten the nut firstly. Once installed with a tool, sleeve anchors can’t be removed so it’s important to hand tighten first to make sure you’re happy with the position.
Happy? Use a wrench or a screwdriver (wrench for the hex or acorn and an appropriate headed screwdriver for the round or flat head anchor) to tighten. Turn three to five times until the installation torque is reached. Do not over-torque as it will compromise the fastening value.
So how many sleeve anchors do you need? Too many fixings, spaced too closely together, can actually reduce the holding power. They should be spaced a minimum of ten anchor diameters apart and be no closer than five diameters from an unsupported edge.
Do increase the spacing when the fastening conditions will vibrate or experience sudden impact as this will lower the interaction of forces created inside the base material.
(Sleeve Anchor Bolt Head)
Types of Sleeve Anchors
There are two common types of sleeve anchors. The main determining design features of a sleeve anchor that change its usage are head style, material composition and diameter.
The nut drive is commonly used for extra strength. It is more common than its flat-head alternative and comes in a variety of finishes. Stainless steel fixings such as the A2 S/S sleeve anchor or the Stainless Steel Loose Nut design are corrosion resistant and are most suited for the external fixture.
Bolt head sleeve anchors are suitable for most types of concrete and masonry, capable of securing medium loads with proper application.
Driven Flat Head anchors are typically used when a flush surface is required. This makes the countersunk sleeve anchor option of fixing more suitable for applications where jutting fixtures can cause inconvenience e.g. when opening doors or attachments could be interrupted or cleaner, hidden fixings is a specified factor.
Flathead anchors are fastened into the hole by a suitable screwdriver head (as opposed to the wrench used for nut driven fixings).
(Sleeve Anchor CSK Head)
How to choose a fixings supplier?
Anchor Fixings are a dedicated company with over 30 years’ experience specialising in the supply of standard and non-standard fixings to the construction and related industries throughout Ireland and the UK.
We provide a personal and speedy service with precise and reliable account management to make sure you’ve got all the supplies you need to reduce downtime and increase productivity. Especially because we can deliver directly to your site.
Browse our fixings range and take advantage of our easy-to-use enquiry basket and get a quote from us in no time.
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This article was written by Anchor Fixings Director Andy Walker.