How much does a 4-person hot tub weigh?

When choosing a spa hot tub for home or outdoor use, weight is often an overlooked but crucial factor. This is especially true for 4-person spa hot tubs, which are both moderately sized and widely popular. However, their own weight and the total weight when full of water directly impact the ground load-bearing capacity, installation location, electrical planning, and transportation arrangements.

Many users ask before purchasing: How much does a 4-person spa hot tub actually weigh? What is the weight of an empty tub? How much weight will it gain when filled with water? Is additional foundation reinforcement required?

    ——LOVIA SPA, headquartered in Guangdong, China, covers an area of 45,000 square meters and employs over 20 experts and 200 workers. LOVIA SPA is one of China's leading and largest manufacturers, suppliers, and exporters of outdoor spa bathtubs and swimming spa bathtubs.

What is the standard weight of a 4-person spa hot tub?

LOVIA SPA 4-person spa hot tub specifications:

• Dimensions: 1810 × 1810 × 770 mm

• Dry weight (empty tub): 230 kg

• Total weight when filled with water: 1130 kg

This means that, in addition to the 230 kg of the tub itself, the water accounts for approximately 900 kg, which is the main component of the spa hot tub's weight.

Why is a 4-person spa hot tub so heavy?

The reason is simple:

The density of water is 1 kg/1 liter.

If the spa hot tub has a volume of 900 liters, it means the water weighs 900 kg. Kilograms.

Hot tubs for spas require a relatively large water volume to provide sufficient soaking depth, a massage circulation system, and jet pipes, resulting in a significant increase in total weight.

Why does a 4-person hot tub for spas only weigh 230 kg dry?

Compared to large 6- or 8-person hot tubs, 4-person models have a more compact structure, making them relatively lighter when empty.

The dry weight of a hot tub for spas mainly comes from:

1. Fiberglass or acrylic tub body

2. Nozzles, pump, heater, and other equipment

3. Insulation layer and base material

4. Outer wooden or plastic shell

4-person hot tubs are typically smaller, have fewer components, and shorter piping, resulting in a significantly lower dry weight than larger family models.

230 kg is a very typical and reasonable weight for a 4-person model.

Why does a hot tub full of water weigh 1130 kg?

Calculation as follows:

1. Empty tub weight

230 kg

2. Water weight

1130 - 230 = 900 kg

This indicates the effective water volume of the spa hot tub is approximately 900 liters (900 kg).

Considering its dimensions of 1810 × 1810 × 770 mm, this water volume is very reasonable, as the effective water filling depth for a 4-person spa hot tub is generally between 55–65 cm, resulting in a volume of 700–1000 liters.

Therefore, the total weight of 1130 kg fully complies with international standards for spa hot tubs.

Will the weight of the spa hot tub when full of water exceed the floor's load-bearing capacity?

This is one of the most important installation concerns for users.

The typical floor load-bearing capacity is:

• Indoor floors: 200–350 kg/m²

• Outdoor terraces/balconies: 250–400 kg/m²

• Concrete floors: Over 1000 kg/m² is not a problem.

The bottom area of the LOVIA SPA 4-person spa hot tub is approximately:

1.81 m × 1.81 m = 3.2761 m²

Total weight 1130 kg → Average load-bearing capacity:

1130 ÷ 3.2761 ≈ 345 kg / m²

Results:

• Most surfaces can support the weight of a 4-person hot tub.

• If placed on a balcony, it is recommended to consult a structural engineer for further confirmation.

• If placed on grass or soil, a concrete foundation must be laid.

Therefore, this weight is within the bearing capacity of common building structures.

What will the total weight of the hot tub be after two adults enter?

This is also a common question.

Assume the average weight of the two adults is 70 kg.

Additional weight:

70 × 2 = 140 kg

Total weight becomes:

1130 + 140 = 1270 kg

This shows that even with 4 people entering simultaneously, the total weight will not exceed 1500 kg. The weight is approximately 230 kg, therefore the load-bearing requirements of the installation area are still within a controllable range.

What are the main components of the weight of a spa hot tub?

The total weight of a 4-person spa hot tub typically consists of the following four parts:

1. Tub weight (dry weight)

Composed of acrylic sheet, fiberglass reinforcement layer, insulation layer, and outer shell.

2. Water weight (heaviest part)

Typically accounts for 70–85% of the total weight.

3. Weight of bathers

The more people bathing, the greater the total weight.

4. Residual water inside the pipes

Even after draining, there will be 5–20 kg of residual water.

Therefore, these factors must be taken into account when calculating the weight of a spa hot tub.

Does weight affect the transportation and installation of a spa hot tub?

Of course.

A spa hot tub with a dry weight of 230 kg requires:

• At least 3–4 adults to carry it.

• A small forklift, tow truck, or roller platform may be needed.

• When entering narrow spaces, it's necessary to measure the passageway beforehand.

Knowing the weight of the empty tub is crucial for installers, as all movement work occurs before filling with water.

Does the floor for a 4-person hot tub need reinforcement?

This depends on the installation location:

1. Outdoor patio, concrete floor → Generally no reinforcement needed

Concrete has a high load-bearing capacity, far exceeding the total weight of the hot tub.

2. Wooden platform → Reinforcement recommended

Wooden platforms are not structurally stable and must be consulted with the contractor beforehand.

3. Balcony or terrace → Engineer assessment required

Although the weight is distributed, structural safety still needs to be confirmed.

In short, weight is the decisive factor in determining whether foundation reinforcement is needed.

Relationship between weight and size (using LOVIA SPA as an example)

The dimensions of the LOVIA SPA 4-person hot tub are:

• 1810 × 1810 × 770 mm

This size is a compact structure, suitable for:

• Small garden

• Balcony

• Unused indoor space

• Small Vacation Home

The water weight corresponding to this size is approximately 900 kg, which is very reasonable and falls within the global standard range of 750–1100 liters for 4-person hot tubs.

This means that the LOVIA SPA 4-person hot tub meets international standards and does not suffer from over-design or insufficient water capacity.

Key Factors Affecting the Weight of a Hot Tub

To help consumers assess more accurately, it's helpful to understand the actual components of the weight:

1. Material Structure

Different brands use different materials, such as:

• Acrylic thickness

• Base material (stainless steel, composite materials, etc.)

• Insulation layer density

• Outer wood panel thickness

The LOVIA SPA uses reinforced acrylic and a multi-layered structure, resulting in a dry weight of 230 kg, typical for a high-quality 4-person hot tub.

2. Water Depth and Effective Water Capacity

Hot tubs are not filled to the rim, typically leaving a 10–15 cm overflow preventer. Therefore, the effective water depth affects the final weight.

3. Seat Structure Design

A deeper seat occupies some internal space; therefore, for two models of the same size, a more complex seat will result in a slightly lower water capacity.

4. Number of Nozzles and Piping System

The more nozzles, the more powerful the pump, and the more complex the piping, the higher the empty cylinder weight.