How Much Hardie Board Siding Do I Need

How Much Hardie Board Siding Do I Need? A Comprehensive Guide

Choosing Hardie board siding for your home is a smart investment. It's durable, low-maintenance, and offers excellent protection against the elements. But before you start your project, one crucial question needs answering: how much Hardie board siding do you actually need? Underestimating can lead to costly delays, while overestimating impacts your budget. This comprehensive guide will walk you through the process of accurately calculating your Hardie board siding needs, saving you time, money, and frustration.

Understanding the Calculation Process

Accurately calculating your Hardie board siding requirements involves more than just measuring the surface area of your home. Several factors influence the final amount, and ignoring them can lead to significant discrepancies. These factors include:

1. Measuring Your Home's Exterior Walls

This is the foundational step. You'll need to measure the total surface area of all the exterior walls that will receive Hardie board siding. This includes:

• Wall Heights: Measure the height of each wall from the foundation to the roofline. Account for any variations in height.
• Wall Lengths: Measure the length of each wall. Remember to account for any projections or recesses.
• Windows and Doors: Carefully measure the dimensions of all windows and doors. These areas will not be covered by siding, so they need to be subtracted from the total wall area.
• Corners and Trims: Consider extra material for cutting around corners, windows, and doors. Overestimating in these areas is better than running short.

Pro-Tip: Use a measuring tape and a notepad to record all your measurements meticulously. Drawing a simple sketch of your home's exterior can also be incredibly helpful. Label each wall with its dimensions.

2. Calculating the Surface Area

Once you have all your measurements, calculate the surface area of each wall using the formula: Area = Length x Height. Remember to subtract the areas of windows and doors from each wall's total area. Then, add up the areas of all the walls to get the total surface area needing siding.

Example: A wall measuring 10 feet high and 20 feet long has a surface area of 200 square feet (10ft x 20ft = 200 sq ft). If a window of 3ft x 4ft (12 sq ft) is on this wall, the area to be sided is 188 sq ft (200 sq ft - 12 sq ft).

3. Considering Waste and Overlap

This is where many DIYers fall short. You'll inevitably have some waste during cutting and installation. Factors such as the complexity of your home's design, your skill level, and the type of Hardie board (lap siding requires more overlap than other styles) all contribute to waste.

Recommended Overages:

• Simple designs: Add 5-10% to your total calculated area to account for waste.
• Complex designs (many angles, corners, etc.): Add 10-15% or even more.
• Beginner DIYers: Add 10-15%, even for simpler designs.
• Lap Siding: Add extra to accommodate the significant overlap required for proper installation.

4. Accounting for Different Siding Types

Hardie board comes in various profiles, each influencing the amount needed. The most common types include:

• Lap Siding: This style has horizontal overlaps, resulting in more material usage compared to other styles due to the overlapping.
• Panel Siding: Larger panels reduce waste, but careful planning is still essential for accurate calculations.
• Shingles: These require precise measuring and cutting, necessitating a slightly higher waste allowance.

Pro-Tip: Check the manufacturer's specifications for your chosen Hardie board profile. They may offer guidelines on waste percentages specific to their products.

5. Factor in Additional Materials

Don't forget the extras! You'll need:

• J-channel: Used to finish the edges of the siding.
• Corner boards: For neat corner finishes.
• Flashing: To protect against water intrusion.
• Nails or screws: Choose the appropriate fasteners for your Hardie board type.
• Caulk: For sealing gaps and ensuring a weathertight installation.

These materials aren't included in the initial siding calculation and should be purchased separately, based on the length of your perimeter and the number of corners.

Step-by-Step Calculation Example

Let's say you have a simple rectangular house:

• Wall 1: 20ft (length) x 10ft (height) = 200 sq ft
• Wall 2: 20ft x 10ft = 200 sq ft
• Wall 3: 30ft x 10ft = 300 sq ft
• Wall 4: 30ft x 10ft = 300 sq ft

Total Wall Area: 200 + 200 + 300 + 300 = 1000 sq ft

Let's assume you have a total of 100 sq ft of windows and doors.

Area to be sided: 1000 sq ft - 100 sq ft = 900 sq ft

Adding a 10% waste allowance: 900 sq ft x 0.10 = 90 sq ft

Total Hardie board needed: 900 sq ft + 90 sq ft = 990 sq ft

Remember, this is a simplified example. A real-world calculation will require more detailed measurements and consideration of various factors mentioned above.

Seeking Professional Help

If the calculations seem overwhelming or your home's design is intricate, don't hesitate to consult a professional. A contractor specializing in exterior siding can accurately assess your needs and provide a detailed estimate. They'll factor in all the complexities, ensuring you have the right amount of material and avoiding costly mistakes.

Optimizing Your Hardie Board Usage

Beyond accurate calculation, you can optimize your Hardie board usage through smart planning:

• Careful Measurement and Cutting: Minimize waste by precisely measuring and cutting the boards.
• Efficient Layout: Plan the arrangement of the boards to minimize cutting and maximize the use of full-length pieces.
• Board Orientation: Orient the boards to minimize cuts and waste. Consider the orientation of your house and sun exposure to help with this planning.
• Utilize Scraps: Save and utilize smaller scraps for areas requiring smaller pieces, such as around windows and doors.

By following these tips, you can further reduce material waste and save money on your Hardie board siding project.

Conclusion

Calculating the precise amount of Hardie board siding needed for your project involves meticulous measurements, careful planning, and consideration of various factors. While a precise calculation isn't always possible without professional assistance, this guide provides a robust framework for a realistic estimate. Remember to always add a contingency for waste, and don't hesitate to seek professional help for complex projects. Proper planning and accurate calculations ensure a smooth, efficient, and cost-effective installation. With the right approach, you can confidently tackle your Hardie board siding project and enjoy the beauty and durability of this high-quality product for years to come.