Roof Design Considerations

Roof Pitch is the number 1 factor in roof design

A roof with a 12/12 pitch that looks aesthetically pleasing can add as much as 50% or more to the initial cost of a roof when compared to the same house with a 4/12 pitch.
Why does a steeper pitch add so much to the price? We are going to compare a 12/12 pitch to a 4/12 pitch. 12/12 has 37.5 % more roof area
12/12 roofing labor is 50 % + per labor per roofing square
Rafter and sheathing labor is 50% more
Roof framing lumber is more

Other factors that add to the increased price can include:
Taller chimney
More attic ventilation
Increased painting costs
Increased stucco or siding costs
Roof maintenance costs, although the need is less frequent.
On the plus side most roofing materials can last 50% longer

This means that if you are going to use a steeper pitch it would be wise to use one of the better top end roofing materials available.

What size roofing nails do i need

Roofing Nail Sizes

What size roofing nails to use


Composition Shingles
Comp Shingles Sheathing Thickness
3/8″ 1/2″ 5/8″ 3/4″
3-Tab comp shingles (Bare sheathing) 1″ 1″ 1″ 1″
Dimensional comp shingles (Bare sheathing) 1″ 1-1/4″ 1-1/4″ 1-1/4″
3-Tab comp shingles over 3 Tab comp shingles 1-1/4″ 1-1/4″ 1-1/4″ 1-1/2″
Dimensional comp shingles over 3 Tab 1-1/4″ 1-1/2″ 1-1/2″ 1-1/2″

*More than 1 layer of roofing not recommended over 3/8″ Sheathing

Wood Shakes(minimum 3/4 ” sheathing)
Wood Shakes Nail Type Minimum Length
18″ Straight Split 5d Box 1-3/4″
18″ and 24″ Handsplit and Resawn 6d Box 2″
24″ Tapersplit 5d Box 1-3/4″
18″ and 24″ Tapersawn 6d Box 2″


Wood Shingles (minimum 3/4 ” sheathing)
Wood Shingles Nail Type Minimum Length
18″ Straight Split 3d Box 1-1/4″
18″ and 24″ Handsplit and Resawn 4d Box 1-1/2″

The above nail sizes are recommendations only. Consult your local building department for specific nailing applications.

Roof return policy

RoofGenius Return Policy

Return Policy Physical Goods
You may return most new, unopened items sold and fulfilled by within 30 days of delivery for a full refund.
We’ll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.). You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days). We’ll notify you via e-mail of your refund once we’ve received and processed the returned item.

International orders
We cannot track shipments outside the USA. We cannot refund shipping costs for orders shipped outside the USA. If we receive the shipped item(s) back we will refund the cost of the item(s), less the shipping costs.

Return Policy Software
You must contact us at within 30 days of purchase to receive a refund on our software. There are certain steps located within our software that will have to be completed to qualify for a refund. We will send you instructions on these steps. After completing these steps we will issue a full refund within 30 days and no longer than 45 days. Be advised that the unlocking code is no longer valid. You must uninstall or stop using any software products for which you no longer posses a valid, purchased license. reserves the right to disable any product keys and/or serial numbers issued to you for the refunded products.

Replace roof mount skylight with curb mounted skylight

Replacing a leaky skylight

Replacing a roof mounted skylight with a curb mounted skylight.

This roof mounted skylight has leaked and been repaired many times. We decided to replace it with a curb mounted skylight and stop the problem once and for all.

Problem Skylight
Problem skylight

New Skylight


First we cut thru the 2 layers of existing shingles at least a foot wider than the skylight. We use an electric circular saw with an old saw blade turned backwards to cut the shingles. We remove the shingles exposing dry rotted sheathing caused by many years of leakage. We Find we need to to remove more shingles to get to rafters past the dry-rot.


Roofing removed
Roofing removed

We replace the dry rotted sheathing. We leave the old skylight in place to prevent dust and debris from entering the house. We use a blower to blow off the dust.

Sheathing Replaced
New osb sheathing installed

We create new sheet metal top and bottom flashings. Unfinished bottom flashing is shown here. A sheet metal shop can make these for you. The bottom needs at least 6′” of metal on the roof lip side. The top requires at least 12″ on the roof side. The more the better. Sheet metal step flashings are woven between the shingles on the sides.


Bottom flashing (unfinished)

We decided to use a skylight 2 feet bigger than our opening to reduce inside finish work. We create a 2″ x 6″ frame and fasten it to the roof. We installed some shingles between frame and roof to reduce a sag in the roof. We install new underlayment and shingles using new sheet metal top and bottom flashings and step flashings woven between roof shingles.


Frame secured to roof

Inside view of new skylight.
Skylight inside view

Roofing Custom proposal writing software

Sample Roofing Proposal

This fictitious example roofing contact-proposal was created with RoofCalcWriter and is provided as an example.
This example uses the following layout; Logo on the top left and brown lettering to the right of logo and bold blue highlight text in different places in the document. All can be changed to fit your needs. Once your design is complete and saved copy it to your invoices and other documents. After your design is complete it is just a matter of a few clicks to produce professional documents.


Roof pitches that can be walked

Roof pitches you can walk on

Do not attempt to walk on these roofs on any pitch !
Moss on a roof that is wet from dew or recent rain.
Frost, snow or ice on the roof

What roof pitch that can be walked on can be determined by many things. Including the following:

Clean and dry soft soled sneakers are usually the best.

Roofing material type
Many materials give better foot grip than others
Concrete tile comes in many textures and designs.
Slate tile is smooth and more slippery than shake tile that has a rough surface

Roofing material condition.
Worn roofing materials can affect on your footing (especially composition shingles with loose   granules) or wood shakes that can be worn and loose and may slide out.

In this example we will use the most widely used roofing material in good condition:
Composition Shingles
Roof Pitch 3/12 to 6/12
Can be walked easily

Roof Pitch 7/12
Can be walked easily, but with caution

Roof Pitch 8/12 to 10/12
Can be walked, but with extreme caution and not advisable.

Roof Pitch 12/12 and above
Cannot be walked on

See Visual Examples of roof pitch: Here
How to determine your roof pitch: Here

In no event will RoofGenius be liable for any incidental, indirect, consequential or special damages of any kind, or any damages whatsoever, including, without limitation, those resulting from loss of profit, loss of contracts, goodwill, data, information, income, anticipated savings or business relationships, whether or not advised of the possibility of such damage, arising out of or in connection with the use of this website or any linked websites.

Internet/Email Service Providers POP3 Servers

Internet/Email Service Providers POP3 Servers

Service Provider
Pop Server
BT Connect
BT Internet
Direct Connection

If you do not find your pop server here, contact your ISP (internet service provider)
Or search the web.

Plywood Osb helper tool

Carpenters-Roofers OSB-Plywood Shingle Tool
This tool will help you install OSB or plywood and comp shingles


Roof Valley markingRoof Valley angle

Eliminates the need to measure valleys to get the proper angle. Simply set the tool in the valley turn the arms to the angle of your valley and tighten. Use this angle to mark your next sheet of OSB or plywood.
Get a perfect cut every time.


osb eavesoab eave

One man can easily install the bottom row of OSB or plywood at the eaves. Tack it to an existing sheet at the eaves leaving a few inches of the slide arm extending out. Slide you next sheet against it and it will hold that end. Never fight the sheets at the eave again.

Cut Shingle Patterns

Cut shingle patterns

This tool is marked every 5-5/8 inches. Set it on your shingles cut on the marks. Cut perfect 5-5/8 patterns every time.

Lay out shingle courses

Shingle row spacingLay out courses that extend from the main run of a roof past a valley. Simply measure from the top down to the first course that crosses the valley. Take this measurement to the short part of the roof and make a mark. Set the OSB-Shingle helper tool on the mark. Mark the roof at the bottom mark on the OSB-Shingle helper tool. Move the OSB-Shingle helper tool down to this mark. Continue this process until you reach the bottom of the valley. This will be the starting point of your courses of shingles. In the case of a protrusion thru the roof such as a dormer, the same procedure can be used.
By marking the roof with the OSB-Shingle helper tool short courses can be avoided.

Made of sturdy 1/8″ aluminum

This item no longer for sale
U.S residents only