Cantilever umbrellas (also known as offset umbrellas or sometimes side mount umbrellas) are beautiful, dynamic pieces of patio furniture that can elevate the decor of a deck or garden space. They seem to float unsupported in the air. Proper support of this style umbrella is key to making the whole system work. No one wants the umbrella falling over on grandma’s head during a gusty summer afternoon!
In this guide, we will go over how to anchor an offset umbrella.
Cantilever Umbrella Wind Problems
Because cantilever umbrellas are designed in a lopsided way, errant wind gusts can quickly destroy an umbrella that isn’t fully secured. Unfortunately, some umbrella companies don’t make it completely clear that buyers usually can’t just open up the included cross base and call it a day.
There are a variety of ways to secure an offset/cantilever umbrella, and this article will cover a few of those options and a few different circumstances. Specifically, it will focus on DIY universal weight options. For off-the-shelf cantilever umbrella bases, click here.
How to Anchor an Offset Umbrella
In order to determine how to secure a cantilever umbrella, you need to consider the following:
- Mobility requirements
- Flooring material
- The umbrella base
- Options for weighting and bracing your umbrella
Depending on individual needs, there are multiple paths to get a good, secure umbrella base. In this article, we will look at these options in detail.
One of the first questions to consider when preparing to create a base for your cantilever umbrella is: does the umbrella need to be moved frequently, or is it going to be pretty much stationary for most of the time?
If you are planning on moving it around, you will most likely want to go to one of the mobile cantilever umbrella base options shown here. These designs are easy to move and don’t involve permanent anchors.
If you really don’t want to purchase a base, there are a few options for DIY mobile bases below, but they generally aren’t as clean and easy as the fixed options.
If you plan on mostly leaving the umbrella in the same spot, you have a great deal more flexibility in how you secure your offset umbrella, as you can think about more permanent fixes.
We must next consider the type of material the cantilever umbrella will be sitting on in order to determine the best support system. Common substrate materials would be concrete, wood decking, composite decking (Trex, concrete pavers, and grass. Each of these materials must be dealt with slightly differently, and each presents different options and opportunities.
Offset Umbrella Mount to Concrete
Concrete is one of the most functional patio materials and can be strong support for a cantilever umbrella. If the concrete is not poured yet, you’re in luck. You can simply sink bolts into the concrete where you want the umbrella to sit. When the concrete is set, add locking nuts to the bolts and you’re good to go. You have to be very careful to get the bolts in the exact correct location, and once installed, the umbrella will be immobile. However, you end up essentially using the entire concrete patio as your umbrella base, so it’s really strong!
If you have a concrete slab already poured, you’ll need to drill into the slab with a hammer drill and a carbide bit, at least 1/2″ deeper than the intended depth of the bolts. You then clean out the hole and insert the bolts from there. This process is a bit of a hassle, as many people don’t have a hammer drill handy. If necessary, you can rent one from your local home improvement center.
But once it’s in, it’s pretty solid.
Cantilever Umbrella Deck Mount (wood)
Wood Decking is one of the easier materials to deal with, as it’s not difficult to drill into as concrete is. Typically wood decking is made of pressure treated pine, cedar, mahogany, or fir. To secure an umbrella to a wood deck you’ll want to use lag bolts, as explained in the section below. Drill into the wood deck at the appropriate locations, and insert lag bolts in order to hold the umbrella.
This method is simple and strong, but it makes it difficult to move the umbrella if you like to have flexibility in arranging your space.
It also means permanent holes in your decking.
Cantilever Umbrella Deck Mount (composite)
Composite decking is a relatively new decking material, recycled plastic (PVC), and glues. There are now many brands of composite decking, but Trex is by far the most popular. This material is durable, long-lasting, and strong. Composite decking is a bit more finicky to work with than wood decking, but if you wish to use lag bolts into composite decking, you can secure an umbrella to a deck in this manner.
You should pre-drill the holes that the lag bolts will ultimately be inserted into, as this is best practice when working with composite materials.
Offset Umbrella Mount to Concrete or Stone Paver Blocks
Concrete or stone paver blocks are a good choice for a backyard patio and can be excellent cantilever umbrella bases as well. If you have not yet built your patio, then you could consider incorporating the cantilever umbrella base into the actual patio blocks themselves, and insert the base while the patio blocks are being laid. Let the base sit underneath the patio blocks, and hide it from sight.
This would give a completely flush look and would work well.
If the patio is already installed, you could lift up some patio blocks and sneak the base under the blocks before replacing them, but you’ll have to do some work to get everything level and smooth.
Alternately, you could add an additional layer of patio blocks solely to weight your cantilever umbrella. This path would be easier, but would not look as clean.
Cantilever Umbrella on Grass
Grass is a difficult material to attach a cantilever umbrella to, as there’s nothing to drill into. Your best bet is to go with an off the shelf cantilever umbrella weight.
You could theoretically use a beach umbrella sand anchor on a lawn, but it would be hard to install and fairly weak. It’s best to purchase a base or create a small area of patio blocks on the grass in order to support the cantilever umbrella.
Cantilever Umbrella Cross Bases
Virtually all offset umbrellas include a metal cross base as part of the package, which is literally a cross made of metal. Many buyers assume that this base is all that is needed to hold a cantilever umbrella, and then they complain when the umbrella collapses on them! These cross bases can be supported in multiple ways, such as is shown in the adjacent image. These bases are usually included in a cantilever umbrella package, but individual items can vary.
These cross bases can be secured in myriad ways. A partial list of these ways is:
- With lag bolts
- Using patio blocks
- Using sandbags,
- Using concrete blocks
- Using water-filled support tubs.
This guide is really only applicable to those umbrellas that use a cross base. Some of the pre-built customized umbrella weight options work without a cross base, so if you don’t have a cross base or don’t want to use one, we suggest you check out the options in that link.
Umbrella Support Systems
Here we will look at several different options to secure a cantilever umbrella to its base material. We will examine lag bolts and screws, patio blocks, concrete blocks, and sandbags.
Support Base With Bolts or Screws
This method really only works if you are putting the umbrella on a wood or composite deck, or are pouring a concrete pad and can embed these lag bolts in the pad. Also, this path only works if you aren’t planning on moving the umbrella much.
Essentially you just purchase lag bolts for each leg of the cross and drill them into the deck. Ensure that the lag bolts or screws will fit the holes of your cross base before installing. Drilling into existing concrete is a bit more complicated than drilling into wood, and will require a ram drill with a carbide bit, and perhaps TapCon style bolts.
Drill into the concrete at least 1/2″ beyond the depth of the lag bolt or screw you are planning to install. Clean out any dust from the holes before you add your lag bolts. This method is a bit of a pain, but if you have the proper tools, it is possible to drill into concrete and add bolts to secure your umbrella to the existing concrete. If you can do it, this method is quite solid.
Support Base with Patio Blocks
Using patio blocks to support the cross base is a more flexible, and less permanent option to secure an offset umbrella than by using lag bolts. Patio blocks, often available inexpensively at local home improvement stores, can fit over the flat metal flanges of the cantilever umbrella base and secure the unit.
Many of the side-mount umbrella manufacturers recommend using four 16″ patio blocks, for a total weight of over 100 lbs, to support the umbrella on windy occasions. If you already have a patio built, you may be able to pull up the blocks and insert your cross base under the blocks, then re-lay them into the patio for a flush look.
If you want to use patio blocks, but you find that they don’t stay situated in the cross base as well as you would like, you could consider getting some masonry adhesive and gluing the patio blocks to the cross base. Masonry adhesive is commonly available at most home improvement stores as well and is typically installed with a caulking gun. The problem with glue is that it makes moving the umbrella much more difficult.
Support Base with Concrete Blocks
Another way to support the base is to use concrete blocks (note: don’t use the lighter cinder blocks) in place of patio stones. The concrete blocks can sit in the metal flanges of the cross base as well. The interior of the concrete block can be filled with stone or sand for additional strength.
Like the patio blocks, you may want to glue the concrete blocks to the cross base with masonry adhesive if you find the concrete blocks shifting around too much. The downside to this is that it makes it harder to move the umbrella around.
Concrete blocks are not the most attractive option, but they do function to hold the umbrella and are quite inexpensive. These result in very much a DIY cantilever umbrella base look!
If you like the cost aspect of concrete block but don’t really like the look, there are a few paths you should consider. You could:
- Add small plants or other decorations to the top of the concrete block
- Paint the blocks in interesting colors in order to take the emphasis off of the fact that they are concrete blocks
- Use a cover to conceal the blocks
However, remember these blocks are big and heavy, and if a flip-flopped toe hits one of these blocks, it will hurt!
Support Base with Sandbags
You can simply lay heavy sandbags over the cross base, such as these 50lbs bags of Quickrete Sand from Lowes. Sandbags don’t sit flush the way the patio blocks might, but they do offer low expense and ease of movement for those who like to move their umbrella to different parts of the patio at different times. This solution is generally temporary, though it is extremely functional and quite simple.
However, if these bags break, you’ll have a sandy mess to clean up, so keep that in mind. If you like the sandbag idea, you could consider getting specialized patio furniture weight bags that are strong, and unlikely to tear.
If you like the inexpensive aspects of this solution, you may consider getting a cloth cover for the sandbags, and hiding them under a colorful blanket or other cloth.
Conclusion: DIY Cantilever Umbrella Base or Pre-Made?
These weight options are all relatively inexpensive and easy to implement. For more customized cantilever umbrella weight options (and more expensive), please read this article.
Without some sort of support system, your beautiful cantilever umbrella will flop over in the wind, break, or smash someone on the head. Be sure to properly secure and weight your umbrella to the weight requirements shown in the specs or manual of your umbrella.
Get it right, and your cantilever umbrella will shade you in style for years!
Best of luck.