Choosing The Right Thickness Of Aluminum For Your Boat Deck

When it comes to boats, the thickness of the aluminium used for the deck is a crucial consideration. While some boat enthusiasts opt for thicker aluminium to ensure a sturdier structure, others prioritise weight reduction and opt for thinner material. The decision is often influenced by factors such as the intended use of the boat, the spacing of the ribs, and personal preferences regarding flexibility and weight distribution.

Using foam underneath aluminium boat decking

When building or refitting a boat, it is important to consider the thickness of the aluminium used for the boat deck. Using aluminium sheeting instead of wood can help save on weight. However, it is crucial to ensure that the aluminium is thick enough to support the weight of people and equipment.

One way to enhance the strength and stability of an aluminium boat deck is to use foam underneath the decking. This technique has several pros and cons that should be considered before implementation.

One of the main benefits of using foam underneath aluminium boat decking is that it provides additional flotation. This is especially important for boats under 20 feet in length, which are required by the US Coast Guard to have flotation devices. Foam also adds rigidity to thin aluminium floors, reducing flex when walking on them. Additionally, foam can dampen vibrations and make for a smoother ride.

When choosing the type of foam to use, it is essential to select closed-cell foam instead of open-cell foam. Closed-cell foam is less likely to absorb water, which can add weight to the boat and affect its performance. It is also important to ensure that the foam is sealed in plastic to protect the aluminium from corrosion.

Another consideration when using foam underneath aluminium boat decking is the thickness of the foam. Thicker foam will provide more support and flotation but will also add weight to the boat. It is crucial to strike a balance between thickness and weight to ensure optimal performance.

Some boat owners have used rigid insulation foam or "pool noodles" as a cost-effective alternative to traditional flotation foam. These materials can provide adequate support and flotation while also being easy to cut and fit to the shape of the boat. However, it is important to ensure that any adhesive used will not affect the foam and that the foam is securely attached to the boat to avoid shifting or dislodging.

In conclusion, using foam underneath aluminium boat decking can provide several benefits, including added flotation, rigidity, and vibration dampening. However, it is important to carefully consider the type and thickness of the foam, as well as the method of installation, to ensure optimal performance and weight distribution.

Aluminium boat decking vs wood

Aluminium and wood are two of the most popular materials for boat decking. Both have their pros and cons, and the best option for you will depend on your specific needs and preferences. Here is a detailed comparison of the two to help you make an informed decision:

Weight:

Aluminium decking is generally lighter than wood, making it easier to transport and install. This can be a significant advantage, especially if you plan to move your dock frequently. However, it's important to note that the weight difference between aluminium and wood decking may not be significant enough to impact your decision.

Maintenance:

One of the biggest advantages of aluminium decking is its low maintenance requirements. Aluminium is highly durable and resistant to rust, twisting, and warping. It requires little to no maintenance beyond occasional cleaning and can last for many years without showing signs of wear and tear. On the other hand, wood decking requires more upkeep. It needs to be power-washed annually and stained or finished every three to four years. Wood is also prone to warping, decaying, and rotting if not properly maintained.

Cost:

Aluminium decking typically costs more upfront than wood. However, it may save you money in the long run since it requires less maintenance. Wood decking can vary in price depending on the type of wood used, and you may need to factor in the cost of maintenance and repairs over time.

Aesthetics:

Wood decking has a classic, natural look that many boat owners prefer. It also feels nice underfoot and can absorb the sun's rays, making it warmer to stand on than aluminium. Aluminium decking, on the other hand, offers a clean, modern aesthetic and is available in various colours, including plain, white, tan, and woodgrain.

Strength and Rigidity:

Wood decking typically offers superior strength and rigidity compared to aluminium. It can bear more weight and is less likely to bend or flex under pressure. However, it's important to note that proper support and framing are necessary for both types of decking to ensure their strength and durability.

Insulation:

Wood and composite decking have better insulating properties than aluminium, providing better heat and sound insulation. This can make a significant difference in comfort, especially if you plan to spend a lot of time on your boat.

Durability:

While both materials are durable, aluminium decking may have a longer lifespan due to its resistance to decay and corrosion. Wood decking can last for many years if properly maintained, but it is more susceptible to the elements and may eventually rot or decay.

Ultimately, the choice between aluminium and wood decking comes down to your personal preferences and specific needs. Both options have their advantages and disadvantages, and the best choice for you will depend on factors such as cost, maintenance requirements, aesthetics, and durability.

Aluminium boat decking thickness gauges

When building an aluminium boat deck, it is important to consider the thickness of the aluminium sheeting to ensure adequate support and safety. The ideal thickness will depend on various factors, including the spacing of the boat's ribs, the intended use of the boat, and the weight of the individuals using it.

Thickness Options

Aluminium sheeting for boat decking typically comes in various thicknesses, ranging from 0.062" to 0.125". The most common thicknesses used for boat decking are 0.062", 0.063", 0.080", 0.090", and 0.125". The thicker the aluminium, the stronger and more durable the deck will be, but it will also add more weight to the boat.

Factors to Consider

When determining the appropriate thickness of aluminium for a boat deck, several factors should be considered:

• Rib Spacing: If the boat's ribs are spaced further apart, a thicker aluminium sheet may be necessary to provide adequate support and prevent sagging.
• Weight: The weight of the individuals using the boat will play a significant role in determining the thickness of the aluminium. Heavier individuals will require a thicker aluminium sheet to support their weight safely.
• Usage: The intended use of the boat will also impact the thickness of the aluminium decking. For example, if the boat will be used for commercial purposes or will carry heavy equipment, a thicker aluminium sheet may be required.
• Flexibility: Some individuals prefer a stiffer deck with minimal flex, while others prefer a more flexible surface. A thicker aluminium sheet will provide a stiffer and less flexible deck.
• Floatation: Adding closed-cell foam or styrofoam between the ribs can provide additional floatation and support, allowing for the use of thinner aluminium sheeting.

Recommendations

Based on the information provided, here are some recommendations for aluminium thickness for boat decking:

• For a balance between weight savings and strength, a thickness of 0.062" to 0.063" is often recommended. This thickness can provide adequate support when combined with closed-cell foam or styrofoam between the ribs.
• For heavier individuals or commercial use, a thicker aluminium sheet of 0.080" to 0.090" may be more suitable. This thickness will provide a stiffer deck and support more weight.
• If weight is not a significant concern and you prefer a stiffer deck, a thickness of 0.125" can be considered. This thickness is less common but will provide maximum strength and durability.

Aluminium boat decking weight considerations

When considering the weight of aluminium boat decking, it's important to strike a balance between strength and weight savings. While a thicker aluminium deck will be stronger, it will also be heavier, which can impact the boat's overall performance and fuel efficiency.

To optimise weight distribution and ensure structural integrity, it's crucial to select the appropriate aluminium thickness for your boat deck. A common recommendation is to use aluminium with a thickness between 0.062 and 0.090 inches. This range offers a good balance between weight savings and overall strength. Thinner aluminium sheets, such as 0.062 or 0.063 inches, can be adequately reinforced by incorporating support structures, such as ribs or side panels, and using closed-cell foam underneath.

However, it's worth noting that some boat owners prefer thicker aluminium for added durability and rigidity. Thicker options, such as 0.125 or 0.100 inches, may be chosen for floors to withstand higher amounts of weight and foot traffic. Additionally, thicker aluminium can be beneficial in areas that require extra strength, such as under fuel tanks and batteries.

The weight of aluminium decking can be further optimised by considering the alloy type. For example, 5052 alloy aluminium is commonly used in jon boats due to its favourable strength-to-weight ratio. Additionally, using aluminium angle framing with a thickness of 1/16th inch can provide crucial weight savings while maintaining overall strength in the boat's structure.

Aluminium boat decking and the support of ribs

Aluminium boat decking and rib support is an important consideration for any boat builder. The thickness of the aluminium decking will depend on several factors, including the size of the boat, the spacing of the ribs, and the desired weight of the boat.

When choosing the thickness of aluminium for a boat deck, it is important to consider the weight of the decking material. Aluminium decking can range in thickness from .062" to .125", with thicker material providing more support and durability but also adding more weight to the boat. One boat builder suggests that 0.062" aluminium sheeting is adequate for boat decking, especially if combined with other methods to stiffen the structure, such as riveting the floor to the ribs, using side panels, or incorporating bends in the material. Another builder recommends using 0.090" aluminium, as it is a good balance between weight and strength.

The spacing of the ribs in the boat will also impact the thickness of aluminium decking required. If the ribs are spaced further apart, a thicker aluminium sheet may be needed to prevent sagging. One builder suggests that with close rib spacing, .062" aluminium sheeting should be sufficient, especially if combined with closed-cell foam between the ribs for added support.

In addition to the thickness of the aluminium decking, the type of foam used between the ribs can also impact the overall strength and weight of the boat. Closed-cell foam wrapped in plastic or styrofoam cut to the same height as the ribs can add floatation and support, reducing the need for thicker aluminium sheeting.

When installing aluminium decking, it is important to consider the method of installation. Riveting the decking to the ribs can provide additional stiffness and support. Additionally, incorporating bends in the material, such as using a press brake to create bent gunwale edges, can also increase the rigidity of the decking.

Frequently asked questions