Refer the below query
;with Employees AS
(
select transdate,
round(isnull(sum(case when CONVERT(float, SUBSTRING (totalhrs,1,2))+ round((CAST( substring(totalhrs,4,2) as float)/60),2) < 8 then
CONVERT(float, SUBSTRING (totalhrs,1,2))+round((CAST( substring(totalhrs,4,2) as float)/60),2) else 10 end ),0),0) as hrs
from timesheetentry
inner join project on projectid = projid
where psno='20006869' and transdate between '2016-07-01' and '2016-07-22' and LN_Proj_Code='DNB045001'
group by transdate
)
SELECT transdate,CASE WHEN hrs > 8 THEN 8 ELSE hrs END AS hrs FROM Employees
Or
SELECT transdate,CASE WHEN hrs > 8 THEN 8 ELSE hrs END AS hrs
FROM (
select transdate,
round(isnull(sum(case when CONVERT(float, SUBSTRING (totalhrs,1,2))+ round((CAST( substring(totalhrs,4,2) as float)/60),2) < 8 then
CONVERT(float, SUBSTRING (totalhrs,1,2))+round((CAST( substring(totalhrs,4,2) as float)/60),2) else 10 end ),0),0) as hrs
from timesheetentry
inner join project on projectid = projid
where psno='20006869' and transdate between '2016-07-01' and '2016-07-22' and LN_Proj_Code='DNB045001'
group by transdate
) q