If you’re limited on space or simply want to take advantage of the beautiful views from your balcony, you’re left wondering whether your balcony is strong enough to support the weight of a hot tub.
It’s possible to put a hot tub on a balcony, but it’s likely to require reinforcement to support the weight. Standard balconies without reinforcement are designed to support between 50-100 lbs per square foot, which isn’t enough to support most hot tubs. Structural engineers can advise you on what work should be carried out.
In this article, I cover:
- How a balcony load capacity compares with your hot tub model
- The best way to strengthen your balcony
- Whether balconies need reinforcement for inflatable spas
Hot Tub Weights vs Balcony Load Capacity
There are a surprising number of preventable incidents where people have put hot tubs on their balconies without checking first.
With most balconies load-rated to 50-100 pounds per square foot (244-488 kg/m2), overloading your balcony is extremely dangerous for you, your guests, and your neighbors.
The weight of the water in a hot tub is by far the greatest concern when trying to decide if a balcony can cope. The weight of the tub is significant, but an empty hot tub should weigh less than two adults.
Add the weight of three people, a hot tub, and the water, and then you have something that weighs between three to four thousand pounds (1300-1800kg).
The water capacity and filled weight will come with the documentation on the tub, so read the texts before continuing.
Can I Put My Hot Tub on My Apartment or Condo Balcony?
The concrete balconies of a modern condo may have specific limitations on how much weight you can load them with.
But it should be easier to find out this weight limit with a newer complex. The plans will also show the best position for the spa and where it can sit near or over reinforced supports.
How to Assess Whether a Balcony Can Hold a Hot Tub
Even a decade ago, building codes were less stringent, and it was easier for contractors to take shortcuts during construction.
An older building will shift over time, and the reinforcing steel running through the concrete will be at varying stages of rusting.
Whether you have a detailed blueprint or not, the best way of figuring out the safety of a hot tub on your balcony is to bring in a structural engineer.
A structural engineer can assess the balcony with ultrasound and come up with solutions if it turns out that the balcony is not strong enough.
How to Strengthen a Balcony to Ensure It is Safe
The strongest place on a balcony will be near a supporting wall, where the door to the balcony is. In an ideal world, you place the hot tub in a corner between two or three supporting walls. You should try to copy the same positioning if you are putting the spa on your roof.
If you doubt the strength of your balcony, or you have confirmation that it will not support the weight, you will need to add bracing.
A structural engineer will give you the best opinion on where to place the spa and the type of bracing to use.
Accidents are common in properties where a resident has put in a hot tub without permission and caused a structural collapse.
Hot tub supports a structural engineer may recommend:
- Simple – Your balcony may have good structural integrity, but uneven distribution may lead to broken tiles and tilting. Simple hot tub mats will help to spread out the weight and protect the original flooring for whenever you decide to take the hot tub away.
- Medium – This will involve seeking permission to tie I-beams into the existing reinforced support beams. The I-beams would then take the weight of the hot tub without the need to rely on the existing floor.
- Involved – You would need permission to update the existing concrete floor and strengthen the beams beneath the balcony. Though it is unlikely that a downstairs neighbor will give you permission to dig out and reinforce their ceiling.
How Is It That Hotels Have Balconies With Hot Tubs?
Hotel hot tubs are popular for parties, but this also means that they need to be far safer than a home hot tub. Accidents can happen on a private balcony, and hotels need to make every effort to prevent injury.
Most hotels will know the weight limits of their balconies, which will be around 50 pounds per square foot (244 kg/m2). These hotels will still need to obtain permission from authorities to install a hot tub.
A hotel will have to install several redundancies for strength, power safety, and flood prevention. A hotel will also need to add a safe way to get in and out of the hot tub and a no-slip fast-draining deck to prevent injuries.
Are Inflatable Hot Tubs Less Weight for a Balcony?
Inflatable hot tubs are convenient because they can disappear for the winter months and give you back your balcony.
However, an inflatable hot tub will puncture, and you’ll also find that it becomes brittle with age. The sun makes vinyl liners prone to cracking, and leaks will become more frequent as the material weakens.
A typical 4-person inflatable hot tub weighs around 100 pounds (45kg). You add in the weight of four people and the water, and it increases to over 2,000 pounds (900kg). This is a lot of weight for a balcony that is designed to cope with basic furniture and a few people.
The lack of a solid wall around the spa will allow water to shift as people get in and out. You may find that constant movement causes waves to develop and water to wash over the edge. Waves in a hot tub can create concentrated areas of weight that may cause issues with your balcony.
Modern building codes force architects and contractors to over-engineer beams and concrete floors. But to be safe, you should still bring in a structural engineer to look at the original plans and integrity of the concrete.
There are several safety issues to consider when installing a hot tub on your balcony. Water and electricity are a lethal combination, so you need the help of several professionals to make sure the spa is fun, safe, and convenient.
Ventilation and Drainage
If you are planning to put the hot tub into an enclosed area of your apartment, you need to consider whether you need to install ventilation.
The ceiling of your balcony, above where you plan to put the hot tub, may collect moisture and go moldy.
A hot tub will need filling up and occasional emptying for maintenance. Even self-cleaning hot tubs need an efficient way to drain during cleaning.
So, to prevent water flooding your balcony, you may want to have both fresh water and drainage plumbed directly to the hot tub.
Some parts of a hot tub will come apart and lessen the weight to make it easier to maneuver onto your balcony. The shape will make it cumbersome, and you are going to need help to bring it into your home.
Larger spas may also need you to bring in a crane or forklift to get it onto the balcony from the outside. You may also need to mention this to the distributor and any committee or property owner that may object.
The electrical requirements can be significant for large hot tubs with power-hungry water pumps, blowers, and heaters.
Power consumption for a typical 4-person hot tub’s pump and heater is around 3,500 watts, but they can consume as much as 7,500 watts.
To put it in comparison, an electric kettle consumes around 1500 watts but will turn off after 5 minutes. A small inverter air conditioner will also consume around 1500 watts.
It is not safe to plug in a high-power hot tub into a regular wall socket, so ask an electrician to update the circuit.
When it comes to the installation, you may need the ability of a professional electrician. The electrician will be able to install sensitive power breakers, better earthing, and rewire cable to manage the load.
If you are renting the apartment, you should start by asking the owner of the property before even bothering to walk into a hot tub showroom.
It may be that the owner does not want the mess, hassle, or a large hot tub taking up space on their property.
Condos and apartment blocks will have building committees. These committees ensure that residents do not alter the appearance and the structural integrity of the building.
You may need to gain permission from the building committee by sending in a structural report to show that you are putting safety first.
Frequently Asked Questions
Can my roof terrace support a hot tub?
Apartment roofs support freshwater tanks, industrial air conditioners, and other loads. This is why roof terraces will have more reinforcements than most balconies. But, if you plan to place the hot tub over the strongest area of the roof, you should still invite a structural engineer in for their opinion.
Is it safe to put an inflatable hot tub on my roof terrace?
A small 30-pound (13.6kg) inflatable hot tub will still weigh 2,000 pounds (900kg) with water, which is a substantial load to put on a roof terrace. You should be able to put an inflatable hot tub on your roof terrace, but you must check the structural limitations of your roof terrace first.