I'd strongly suggest paid hosting. With FREE hosting you often get the age old saying 'You get what you pay for' paying nothing for hosting usually in most cases you wil get no support, advertising on your website (they have to make money somehow), downtime and other issues.
Always much better to have your website on a secure, reliable web server and im afraid that would mean spending a little money
Try the service offered at webhosting.uk.com for your domain i'm sure you would not be disapointed after all 'Customers are always right' and you have to 'speculate to accumulate'
If its a registered charity im sure contacting us to arrange free hosting is no problems we always work very close to charities to help them help others.
Thanks for question and good luck,
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Web Hosting UK Blog | Dedicated Servers VPS Hosting Technology Updates alot more in depth information into this.