What is a Spool?

what is a spool

What is a spool?

In the realm of outdoor relaxation, the pool reigns supreme as a symbol of luxury and leisure. But what if you crave the invigorating benefits of a pool without the expansive footprint and maintenance demands? Enter the spool, an ingenious combination of a pool and a hot tub that offers the best of both worlds in a compact and versatile package. Spool, comes from the combination of two words – small pool.

Spools, also known as plunge pools or cocktail pools, are designed to provide a space for exercise, relaxation, and therapeutic soaking, all within a manageable size that fits seamlessly into even the most modest backyards.

Whether you’re seeking a place to unwind after a long day or a dedicated area for aquatic fitness, a spool presents an ideal solution for those seeking a versatile and space-efficient backyard oasis.

In this comprehensive guide, we’ll delve into the world of spools, exploring their unique features, benefits, and considerations to help you decide if this innovative water feature is the perfect addition to your outdoor haven.


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What are the differences between a swimming pool and a spool?

Swimming pools and spools, also known as plunge pools or cocktail pools, are both popular backyard features that offer refreshing and enjoyable water experiences. While they share some similarities, there are also distinct differences between the two that make them suitable for different needs and preferences.

Size and Dimensions:

  • Swimming pools: Swimming pools are typically larger, ranging from 12 feet by 24 feet to 50 feet or more in length. They are designed for recreational swimming, lap swimming, and hosting pool parties.

  • Spools: Spools are significantly smaller than swimming pools, typically measuring around 8 feet by 12 feet to 10 feet by 16 feet. They are designed for a more intimate experience, focusing on relaxation, therapeutic soaking, and aquatic fitness.

Depth and Shape:

  • Swimming pools: Swimming pools typically have a deeper end to accommodate diving and varying swimming depths. The shape can vary, from rectangular and oval to kidney-shaped and freeform designs.

  • Spools: Spools are generally shallower than swimming pools, typically ranging from 3 to 5 feet deep. The shape is often rectangular or square, with some models featuring integrated seating or raised ledges.

Purpose and Features:

  • Swimming pools: Swimming pools are primarily intended for recreational swimming and pool parties. They may feature additional amenities like slides, diving boards, and poolside lounging areas.

  • Spools: Spools are designed for relaxation, therapeutic soaking, and aquatic fitness. They often feature integrated jets for swimming or water resistance training, as well as built-in seating and temperature control.

Maintenance and Costs:

  • Swimming pools: Swimming pools require more extensive maintenance due to their larger size and volume of water. This includes regular cleaning, chemical balancing, and potential repairs for leaks and damage.

  • Spools: Spools generally require less maintenance due to their smaller size and water volume. However, regular cleaning, chemical balancing, and filter maintenance are still necessary.

Overall, swimming pools offer a larger, more versatile space for swimming, pool parties, and aquatic activities, while spools provide a more intimate and focused experience on relaxation, therapeutic soaking, and aquatic fitness.

Here’s a table summarizing the key differences between swimming pools and spools:

Feature Swimming Pool Spool
Size Larger (12’x24′ to 50′ or more) Smaller (8’x12′ to 10’x16′)
Depth Varies, with deeper end for diving Generally shallower (3′ to 5′)
Shape Rectangular, oval, kidney-shaped, freeform Rectangular, square, with integrated seating or raised ledges
Purpose Recreational swimming, lap swimming, pool parties Relaxation, therapeutic soaking, aquatic fitness
Features Slides, diving boards, poolside lounging areas Integrated jets, built-in seating, temperature control
Maintenance More extensive due to larger size and water volume Less maintenance due to smaller size and water volume
Costs Higher upfront and maintenance costs Lower upfront and maintenance costs

What is the average size of a spool?

The average size of a spool is approximately 10 to 16 feet long and 6 to 8 feet wide. This size range provides a comfortable and functional space for relaxation, therapeutic soaking, and aquatic fitness without requiring the extensive footprint of a traditional swimming pool.

The specific size of a spool will depend on several factors, including the available space in your backyard, the number of users, and your desired level of comfort. Smaller spools are suitable for individual or couple use, while larger spools can accommodate small groups or families.

Here’s a breakdown of spool sizes based on typical usage:

  • Individual or couple use: 8 feet by 10 feet or 10 feet by 12 feet

  • Small group or family use: 12 feet by 14 feet or 14 feet by 16 feet

It’s important to consider the layout of your backyard and the placement of other landscaping elements when determining the appropriate spool size. Ensure that the spool fits comfortably within the available space and doesn’t interfere with walkways, patios, or other features.

If you’re unsure about the ideal spool size for your needs, it’s advisable to consult with a pool and hot tub professional. They can assess your backyard space, discuss your usage preferences, and recommend the most suitable spool size for your specific situation.

Can I build a DIY Spool?

Yes, you can build a DIY spool, but it is a challenging and time-consuming project that requires specialized skills and knowledge. If you are not an experienced DIYer, it is best to consult with a professional contractor to ensure the safety and quality of your spool installation.

Here are some of the steps involved in building a DIY spool:

  1. Planning and Design: Carefully plan the size, shape, and features of your spool to ensure it fits your backyard space and meets your needs. Sketch out a design and consider the placement of jets, seating, and other amenities.

  2. Excavation and Foundation: Excavate the area where the spool will be placed, ensuring a level and stable foundation. Follow proper construction guidelines to ensure the integrity of the foundation.

  3. Plumbing and Electrical: Install plumbing lines for water intake, filtration, and jet systems. Consult a qualified electrician to install electrical wiring for pumps, jets, and lighting fixtures.

  4. Shell and Insulation: Construct the spool shell using durable materials like concrete, acrylic, or fiberglass. Ensure proper insulation to maintain water temperature and energy efficiency.

  5. Jets and Seating: Install jets and seating arrangements according to your design plan. Choose jets that provide the desired water resistance for swimming or fitness.

  6. Filtration and Heating System: Install a filtration system to keep the water clean and clear. Choose a heating system that suits your climate and desired water temperature.

  7. Finishing Touches: Apply finishing touches like landscaping, decking, and lighting to create a cohesive and aesthetically pleasing backyard oasis.

Building a DIY spool requires careful planning, attention to detail, and adherence to safety standards. If you are not confident in your abilities, it is strongly recommended to seek assistance from a qualified pool and spa contractor.

What are the design considerations for a DIY Spool?

Building a DIY spool can be an exciting and rewarding project, but it’s essential to carefully consider various design aspects to ensure a safe, functional, and aesthetically pleasing backyard oasis. Here are some key design considerations for a DIY spool:

  1. Space and Layout:
  • Available space: Determine the available space in your backyard to accommodate the spool and any surrounding landscaping or decking. Ensure the spool fits comfortably without compromising other backyard features or traffic flow.

  • Location and orientation: Choose a location that receives ample sunlight for solar heating potential and consider wind patterns to minimize disruptions to water circulation.

  1. Shape and Size:
  • Shape: Select a spool shape that complements the overall design of your backyard and landscaping. Popular shapes include rectangular, square, and oval.

  • Size: Choose a spool size that suits the number of expected users and the available space. Consider smaller spools for individual or couple use and larger spools for families or small groups.

  1. Depth and Seating:
  • Depth: Determine the desired depth based on your usage preferences. Typical spool depths range from 3 to 5 feet, allowing for comfortable soaking and aquatic exercises.

  • Seating: Integrate built-in seating or ledges for relaxing and socializing within the spool. Consider ergonomic designs and adequate space for comfortable seating.

  1. Jets and Water Features:
  • Jet placement: Strategically place jets to provide the desired water resistance for swimming, fitness, or therapeutic purposes. Consider adjustable jets for customized water flow.

  • Water features: Incorporate additional water features, such as waterfalls or fountains, to enhance the visual appeal and ambiance of the spool area.

  1. Filtration and Heating Systems:
  • Filtration system: Choose a filtration system that effectively cleans and circulates the water, ensuring a hygienic and enjoyable experience.

  • Heating system: Select a heating system suitable for your climate and desired water temperature. Consider energy-efficient options like solar heating or heat pumps.

  1. Materials and Finishes:
  • Shell materials: Opt for durable and water-resistant materials like concrete, acrylic, or fiberglass for the spool shell. Consider the aesthetic appeal and compatibility with your surroundings.

  • Surface finishes: Choose non-slip and aesthetically pleasing surface finishes for the spool interior and surrounding areas. Consider tile, stone, or textured coatings.

  1. Lighting and Aesthetics:
  • Lighting: Install underwater and landscape lighting to enhance the ambiance and safety of the spool area. Consider energy-efficient LED options.

  • Aesthetics: Create a cohesive and aesthetically pleasing design by incorporating landscaping, decking, and decorative elements around the spool.

  1. Safety Considerations:
  • Fencing and gates: Install appropriate fencing and self-closing gates to prevent unsupervised access, especially for children and pets.

  • Handrails and steps: Provide sturdy handrails and steps for safe entry and exit from the spool.

  • Emergency shutoff switches: Install clearly marked emergency shutoff switches for pumps and electrical equipment.

  1. Maintenance and Accessibility:
  • Access panels: Install removable access panels to allow for easy maintenance and repair of plumbing, electrical, and filtration components.

  • Regular maintenance: Establish a regular maintenance schedule for cleaning, chemical balancing, and filter replacement to ensure optimal water quality and system functionality.

By carefully considering these design factors, you can create a safe, functional, and aesthetically pleasing DIY spool that will provide years of enjoyment and relaxation in your backyard oasis.

What are the sanitation considerations for a spool?

Just like swimming pools and hot tubs, spools require proper sanitation to maintain clean and healthy water for swimming, soaking, and aquatic exercise. Here are the key sanitation considerations for a spool:


  • Choose a suitable sanitizer: Select a sanitizer that effectively kills bacteria, algae, and viruses while considering its compatibility with your spool’s materials and usage preferences. Common sanitizers include chlorine, bromine, and salt chlorine generators.

  • Maintain sanitizer levels: Regularly test and adjust the sanitizer level to ensure it falls within the recommended range for safe and effective sanitation.

Chemical Balancing:

  • Balance pH, alkalinity, and calcium hardness: Maintain proper pH (between 7.2 and 7.8), alkalinity (between 80 and 120 ppm), and calcium hardness (between 150 and 250 ppm) to prevent corrosion, chemical imbalances, and skin irritation.

  • Use test kits and balancing chemicals: Regularly test the water’s chemical balance and adjust as needed using appropriate balancing chemicals.


  • Select an effective filtration system: Choose a filtration system with adequate capacity to clean and circulate the water effectively. Consider sand filters, cartridge filters, or diatomaceous earth filters.

  • Clean or replace filters regularly: Follow the manufacturer’s instructions for cleaning or replacing filters to maintain optimal filtration performance.

Shock Treatment:

  • Perform shock treatment periodically: Use shock treatment to eliminate algae buildup and restore water clarity after heavy use or contamination.

Preventative Measures:

  • Cover the spool when not in use: Use a cover to prevent evaporation, reduce heat loss, and minimize contamination from debris and insects.

  • Rinse off before entering: Rinse off swimmers before entering the spool to remove dirt, sunscreen, and other contaminants.

  • Avoid excessive splashing: Encourage swimmers to avoid excessive splashing to minimize contamination from skin and hair products.

  • Maintain proper hygiene: Practice good hygiene by showering before and after using the spool to prevent the spread of germs.

  • Seek professional assistance: Consult a pool and spa professional for guidance on proper sanitation practices, chemical balancing, and maintenance schedules.

By following these sanitation considerations and maintaining proper water care practices, you can ensure that your spool remains a clean, healthy, and enjoyable place to relax, unwind, and engage in aquatic activities.

How much does a spool cost?

The cost of a spool can vary depending on several factors, including size, features, materials, and installation. However, you can expect to pay anywhere from $10,000 to $50,000 for a spool.

Here is a breakdown of the average cost of a spool based on size:

  • Small (8 feet by 10 feet): $10,000 to $15,000

  • Medium (10 feet by 12 feet): $15,000 to $25,000

  • Large (12 feet by 14 feet): $25,000 to $35,000

  • Luxury (14 feet by 16 feet): $35,000 to $50,000

In addition to the cost of the spool itself, you will also need to factor in the following expenses:

  • Excavation and foundation: $2,000 to $5,000

  • Plumbing and electrical: $3,000 to $6,000

  • Jets and seating: $1,000 to $3,000

  • Filtration and heating system: $2,000 to $4,000

  • Landscaping and decking: $1,000 to $5,000

  • Maintenance: $500 to $1,000 per year

As you can see, the total cost of a spool can range from $16,000 to $60,000. However, the exact cost will vary depending on your specific needs and preferences.

Here are some ways to save money on the cost of a spool:

  • Choose a smaller spool: Smaller spools are less expensive than larger spools.

  • Consider a DIY spool: Building a DIY spool can save you money on labor costs. However, it is important to have the necessary skills and experience to do it correctly.

  • Shop around for the best price: Get quotes from multiple pool and spa contractors to find the best price.

  • Look for used spools: You may be able to find a used spool for a fraction of the cost of a new one.

  • Do your own maintenance: Maintaining your spool yourself can save you money on labor costs.

By following these tips, you can save money on the cost of a spool and enjoy the many benefits of having your own backyard oasis.


Can I Help You?

If I can help you in any way I would love to hear from you. You can get in touch using the form below.

Thanks - Andi


Hi, Andi here. I own Buildahottub.com and also write all of the articles and info pages on the site. Some years back now, I built my own hot tub but struggled to find the information I needed. So, once my tub was complete, I started this website to help others in their own pursuit of hot tub and plunge pools DIY building information.

Today, I've helped over 1000 DIY customers just like you all over the world build hot tubs and pools. Have a good look around the site, there are lots of resources here. Please do get in touch if I can help you. - Cheers, Andi

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