It depends on the level of understanding of the developers. Two colleagues
and I have just started a project to revamp a 100-page web site, and one of
the design requirements is excellent accessibility for people with visual
and mobility impairments. Because all three team members are well-versed in
accessibility issues, we anticipate the additional cost to be zero. We did
not even bother to include costs for accessibility designing and testing in
our bid. Planning for accessibility is second nature to us.

If developers are starting with little or no understanding of web
accessibility, 8 or 10% sounds low. I cannot even guess the additional costs
when developers are dealing with accessibility requirements for the first
time, but it is bound to be a lot. I recently project-managed a web
remediation project, working closely with approximately 150 webmasters and
web developers. Their job was to make tens of thousands of existing pages
conform to the requirements of WCAG 1.0. My job involved educating them
about accessibility, assistive technologies, and WCAG, and some spent
significant chunks of time spinning their wheels before cottoning on. When I
began the project, the idea that there are users who cannot handle a mouse
surprised them, most had never seen a screen reader in action, and many did
not even know there was such a thing as a screen reader. So there was a
steep learning curve.

My guess is that 10% - 15% is about right if developers have been through
the process at least once. I would also speculate that additional costs for
accessibility approach zero as developers becoming increasingly familiar
with accessibility requirements, and accessibility becomes engrained in the
development process.

Realistically, there will probably always be some costs associated with
ensuring good accessibility. For the usability testing phase of my current
project, the client has agreed to provide us with a group of blind and
low-vision users with various levels of computer experience. But if the
client had not been able to offer us such good subjects and we had to
organize it ourselves, or if we wanted to test the site with older users,
children, or people without disabilities, that would take more time and
money.

Alan

Alan Cantor
Cantor Access Inc.
[log in to unmask]
www.cantoraccess.com

Hello,

I am interested to here from folks who have actually gone through the
exercise of planning for, costing and implementing accessibility-related
activities into a web development project as part of their project's life
cycle. I was recently quoted a statistic thatstated that this activity
added  8 to 10% on a project's development time.

Does this statistic hold true?

Thanks,
Jennison